Last updated: February 28, 2024

Project Ultimate 83 GTI
Videos # 150 - 181 (May 2017 - Dec 2019)

 

The timeline story of the whole project in videos from beginning to end

 

Part 150 (I drove the GTI out to Mission Raceway last Friday and bolted on the Hoosier DR2 225/50-15 slicks with 10mm spacers and 1" rubber coil spacers to give me barely 1/2" of needed clearance to the wheel wells - and they didn't rub even after lowering to 15psi and doing 5 passes on the strip. Yeah!

The s/w simulator, when loaded with the dyno test results, indicated that when fully dialed in the GTI should get close to 12.3s @ 112mph w/o nitrous, and around 11.5s @ 123mph with 80hp of nitrous. I ran 13.8s @ 104mph. What happened? Lots. I'll be back again on June 16th, weather permitting, which is the next 'test and tune' track date.

Lessons learned from day 1 at the track:

1. I need to increase the rev limiter from 8000 to 8300rpm (I was hitting the rev limiter in each gear for 0.25s before shifting)

2. Install that solid transmission mount to stop the wheels from loading/unloading all the way thru 1st gear

3. Do a bigger ‘proper’ burnout after going thru the water box as the tires were still wet and not gripping properly – drive thru the box and start the burnout on the other side, keep them spinning until there is some smoke

The total damage relative to my software simulated runs...

I ran a 2.3s 60' time rather than a best possible 1.8-1.9s time (0.4s delta) - looking at the ECU datalog it is clear that I wasn't even at 50% throttle for most of 1st gear - and the tires were still spinning like mad, plus the time from throttle off in 1st and back on in 2nd was over 1s ... this kills ET and mph as the car is eating up track distance without any acceleration - I needed only another 30' of track to reach 8000rpm in 3rd which is 111mph with the larger diameter slicks ...

I shifted too slowly each time (0.5s lost total), I hit the rev limiter for about 0.25s in each gear 

I ran 13.8s @ 104mph and it is easy to see that the GTI indeed has the potential for mid 12s 110mph+ time slips on the motor alone ... I need more seat time at the track for sure - this isn't as easy as going to a chassis dyno (it requires skill that I currently lack). Hmm.

And the nitrous wasn't working - I will need to debug the wiring to the solid state nitrous solenoid before heading back to the track. Good thing the nitrous wasn't working though as it would have just made things uglier at the track - I need to dial in the car w/o nitrous first) - May 30, 2017

 

Part 151 (After some more static nitrous system testing I determined that the tiny 5mm OD nylon nitrous line from the trunk to the engine was restricting flow so I removed the jets from the NOS Wizards Quadranoid and used the adjustable plunger to set the flow rate. In the process I managed to rip the o-ring seal and also over tighten the plunger and damage the teflon plunger seat so it was leaking badly - so I ordered a new solenoid and continued with my testing ...

With the plunger seat set fairly close to the fully 'off' position (about 1/2 turn) I ended up with around 65hp of nitrous flow to the engine. PWM control testing showed flow from around 25-80% (below that it doesn't operate and above that it flows around 100%) and it was not entirely linear - as in 50% PWM gave around 40hp of nitrous flow.

Street testing was initially done at part throttle at 30/50/100% PWM setting with manual activation - to verify that things were within an acceptable A/F ratio range. This type of testing has limitations as it is hard to hold the throttle steady enough for consistent ECU performance - the 'CL Comp' value (closed loop compensation of A/F ratio) is very sensitive to TPS (throttle position) so it is only a rough measure of how rich/lean the ECU nitrous programming is. Anyway, it showed that I needed to adjust the nitrous fuel tables up to 30% which I did do.

Street testing at full throttle and 100% PWM was quite a handful: there is NO traction in 2nd gear - within 0.5s the RPM jumps from 3,500 to 7,000rpm as the street tires spin. The tires hold in 3rd gear with a dramatic rush from the sudden increase in torque - it is like a turbo with zero lag. Very impressive. 

Post street testing, a look at the ECU datalogs indicated a 0.1s lean condition on initial nitrous flow so I turned off the default 125ms fuel delay setting - the nitrous was getting to the engine before the fuel was and this was causing the ECU to try and add fuel to compensate, resulting in an over-shoot/under-shoot instability in the A/F ratios for about 1.5s until settling down to my target 13:1 ratio. Things should be much more stable now - and I will find out Friday at the drag strip. And hopefully 2nd gear will hold with the drag slicks.

I also installed a solid rear transmission/motor mount - I modified it a bit with some rubber padding - it does cause increased vibration in the chassis but it is liveable for the limited period of time I will need to have it installed while racing.

Ted/Jetfab made me some nice aluminum ramps to allow me to drive on/off my EZ car lift - it will come in handy when I store the GTI in a single car garage on Vancouver Island this summer.

Finally, I installed a brake duct cooling system and switched over to the Hawk DTC-60 race pads - they are now bedding in and the car is therefore ready for the road course testing this weekend. I also installed the passenger Sparco racing seat and harness so I can have the instructor with me ...) - July 4, 2017

 

Part 152 (I made the epic journey to both the Mission Raceway and the Vancouver Island Motorsports Circuit over the past weekend, towing my GTI with the EZ Car Dolly behind our Highlander. The wheel/tire straps were too large and I didn't realize they were adjustable for width and length so I managed to bang up the control arms and rip at the fender flares but no other towing issues were involved. I have new ordered 'fixed' straps for smaller wheels like mine which should help a lot - the adjustable straps are a pain to use and aren't as secure as fixed straps are.

With the nitrous system working properly I was keen to get some nitrous 1/4 mile passes in. The first baseline pass without ntrous was another 13.8s time slip with some wheel slip again off the line. The 2nd pass was with 33% PWM on the nitrous (around 25-30hp) and I ended up with the clutch slipping in all gears. I thought it was tire slip so I put on the stock wheels and tires to see if the slicks were the issue and the car ran without clutch slipping, but I hit redline in 3rd gear before the 1000 foot mark and forgot to shift into 4th until too late and missed the shift - the car ran a 13.4s time slip so it would have hit high 12s if I hadn't shut-off so early and coasted. But the mystery of the clutch slip remains and I'll have to look into it more later (it didn't surface again at the road course). The fact that my street tires had better traction than my slicks seems to be related to the 1.3 degrees of negative camber - the slicks are very wide (about 9.5") and don't sit flat enough on the road surface. I only had 45 minutes of total racing time available as the track opened late and I needed to drive 100kms to the ferry terminal for a 2pm departure ...

I got to my new GTI storage garage at Parksville and setup everything before the end of Friday night. I washed the GTI and prepped it for the 100kms morning drive to the track early Saturday. The Hoosier tire engineer/sales rep was there to show off the new A7 racing slicks and I was proud to say I had brought my own set of A6 tires (a lower temperature compound version) but I had mistakenly brought only 2 A6s and 2 DR2 drag slicks so I could only run on the street tires on Saturday - I planned on returning Sunday to run with the A6s but disaster struck late in the day for me Saturday ...

My first time around the road course in the GTI was thrilling. My line and technique was rusty and far from perfect but I hustled around the track at speeds higher than the other Porsche Cayman S track cars were capable of. By example, I was 150-155km/h at the top of the track long straight vs 140-145km/h for the Porsche Cayman S cars and had a lap time 5s faster. I had higher acceleration, equal braking, and almost equal corning power (estimate only - no g force data logging to back this statement up - TBD in the future). The suspension was quite neutral so when I overpowered the car into and around the corners the car simply drifted sideways. Yes, there was some typical FWD pushing when I tried to accelerate too hard out of the corners but we were all amazed how well mannered and dialled in the suspension system was for a '1st timer'. I don't think I'll change anything about the suspension. Some other folks drove the car and thought the suspension was too stiff but I felt it was perfect and since it is acceptable on the street and it is dead flat at the track I have zero complaints.

The Tech53 brakes with the racing Hawk DTC60 pads were the highlight of the day at the track - those brakes were awesome! They hauled the car down from 160km/h like I was hitting a tire wall each time. No fade, no modulation issues - just pure high octane stopping power. Wow.

I finally convinced the lead instructor to drive me around the track but he was babying the car too much so I egged him on to rev past 8000rpm and push deeper into the corners, which he finally started to do. He admitted that the GTI 'has very good acceleration'. Then the engine 'note' suddenly developed a raspy edge and I knew something was failing in the engine bay so I madly waved him to pull off the track and killed the engine. I captured all of this on video and you will see that it took a while to find out what was causing the problem: the adjustable cam sprocket had vibrated apart and was only holding together with 2 partially loosened bolts with the sprocket wobbling wildly. I found out later that the issue was the crank damper/pulley fasteners backing off enough to let the pulley get out of balance and that increase in vibration, plus the solid trans mount, put enough added stress on the sprocket, plus the extended 8300rpm use ...

Timing marks were still in alignment but the question will be whether or not my 12:1cr pistons and 34mm intake valves and 288 race cams would allow for wide variations in cam timing and NOT bend all of my expensive valves. I will do a full inspection next week and find out - fingers crossed. I have INA Engineering machining me a new fluidamper with a custom steel spacer and lip press-fit together with new OEM bolts - the substandard aluminum spacer will go in the garbage. I will also install a better cam sprocket and new ABF timing belt) - July 11, 2017

 

Part 153 (All good! Pistons and valves did not appear to touch each other. My initial commentary in my videos indicated otherwise because you can see small shiny areas in some of the intake valve reliefs in the pistons. But Josh, my engine builder, says they are simply camera light reflections on the shiny areas that are from the turbulence caused by the valves coming so close to the pistons during normal use - similar to what happens to the squish area of the combustion chamber where the top of the pistons are shiny too.

I used a bore scope to inspect and take photos of the pistons and then conducted leak down and compression tests on all cylinders. With a 90psi input pressure the leak down for all cylinders was in the 4-6psi range. The compression tests ranged from a low of 180psi to 210psi - again, Josh says that the variability is not an indication of valves being bent - if they had been bent compression would be terrible, same with the leak down results.

I was about to start putting the engine back together when I realized that the beautiful, sturdy new Kent cam sprocket didn't have an integrated key so I got on the ferry and left for the week. I contacted the supplier and they pointed out that there is a half-woodruf key supplied in the box which I didn't notice. In any case, Fred/Tech-53 has lost a few motors from these aluminum sprockets failing (aluminum fatigue around the key area when used with aggressive cam profiles and high rpm) and strongly advises people to steer clear of them. He is sending me one of the modified (and heavier) steel OEM units that are setup for adjustability. I am also going to change my rev limiter to 7,600rpm to avoid punishing my nice motor - it produces its peak power closer to 7,200rpm and so revving up to and past 8,000rpm with my heavy 95.5mm stroker crank isn't necessary or good for the longevity of the motor anyway.

Josh says to only use the cam sprocket adjustability to 'zero' the cam in. When he did it the cam was lined up exactly at 'zero' on the scale so I guess I could simply use an OEM steel sprocket which would be highly reliable. I'll order one as they are not expensive and will also get one of Fred/Tech-53's adjustable all steel sprockets. Josh's comments on advancing the cam to lower the power peak is to not bother as it won't typically help - he wants the cams at true 'zero'.

Another thing Josh pointed out is that people tend to set the cam belt tension too high, causing excessive wear on the 1st cam journal bearing and the intermediate shaft bearings - his point is that once an engine heats up it will expand so the 45 degree finger twist test should be slightly lose when cold) - July 19, 2017

 

Part 154 (Issam at iABED Industries (formerly INA Engineering) made me up a trick custom Fluidamper assembly on a rush basis with many thanks. It consists of a slightly turned out (32mm ID) fluidamper with a press-fit steel 6.2mm spacer that will mount 'hub centic' to the ABA crank sprocket. I will use grade 12.9 allen head bolts, lock washers and locktite 242 and will torque to spec. The aluminum spacer and previous Fluidamper damper will be sold if anyone wants it (it would be fine for a non-race lower rpm motor)) - July 20, 2017

 

Part 155 (I decided after subscriber feedback that the Kent adjustable Cam Sprocket was strong enough to be used so it is now installed, with Locktite 242 and prep spray, torqued a bit higher than the OEM 45 ft-lbs spec, plus I installed a new timing belt as the other one had been thrashed and potentially stretched with the cam sprocket wobbling as much as it had. I installed the custom INA fluidamper assembly with 8x30mm grade 12.9 allen head bolts, lock washers and the same locktite 424/prep spray as for the cam sprocket and torqued it all properly. I then fabricated a new alternator bracket as the other one had snapped when the damper had shifted, and I was keen to sort out a finely adjustable bracket that was stronger - mission accomplished.

After all of the re-assembly work ,measuring the lash of my solid lifters (all within spec and on the tight side @ 0.008-0.010" intake and 0.012-0.015" exhaust) putting the cam cover back on with some RTV, etc. I cranked over the engine with the starter (ignition off) and there was a nasty clicking sound coming from the bell-housing. This sound was not present 2 weeks earlier when I was testing the engine for potential piston-valve damage when I did leak-down and compression testing, but I realized that I had done that testing without spark plugs installed and this was the 1st time I had the engine fully back together and the cranking while under full compression with 12:1 pistons ....

So I looked carefully at the clutch pressure plate and found that it was slightly lose - I could move it back and forth a few degrees so those critical bolts that hold the pressure plate to the crank had also worked a bit lose when the damper had shifted. Who knows, maybe the pressure plate bolts were the 1st ones to back off and the damper bolts worked lose next, then the cam sprocket assembly? I will never know. But I do know that 8300+rpm and my large 95.5mm stroker crank is not a great combination so that is why I am keeping my max rpm to 7,600rpm from here onwards ...

So the car won't be on the road again for a few more weeks as I need to drop the transmission out of it, remove the clutch assembly and install new racing Techtonics/ARP pressure plate bolts. This requires me to source an engine support bar and a transmission hoist which are now ordered. What a pain ... but I did have some significant clutch slippage at the drag strip and there is a lot of black clutch dust all over the inside of the bell housing so I want to inspect the clutch and decide if I need to change or upgrade it further (it is a custom racing clutch but it may need to be stronger if I want to use nitrous with it).

I went to the VIMC track today and rented a 2017 M3 which has the same wt/pwr ratio as my GTI and it was a lot of fun. The car feels heavier for sure (3600lbs vs. 1900lbs) but it has big brakes and lots of low-end torque so it pulls harder out of the corners and seems to have stronger brakes. I will be back on the track with it later this week and will record the lap times and g forces and when I get the GTI to the track I will have comparison data. The M3 is faster than the Cayman S I drove at VIMC ...) - August 6, 2017

 

Part 156 (Hmm. I should have been nicer to my shiny new GTI rather than immediately take it to the drag strip for 20 passes at full throttle, with nitrous and slicks, slipping the crap out of the clutch.

Lesson #1: street cars are meant for the street, race cars are (built) and meant for the strip/circuit track. Yes you can take a street car to the track but it won't like it much, putting a lot of stress and premature wear on all of the critical parts. Either you build a race car that has a race clutch, high rpm engine components (and fasteners) and brakes or you take your street car to the track and you don't massively abuse it or try to run it at 10/10th continuously.

After getting the engine support brace and the transmission hoist setup I pulled the trans out and it wasn't too much work for a single person job. I had more trouble getting the axles out than actually pulling the trans out. When the clutch pressure plate wouldn't come off the crank snout I knew I was in trouble. Yes, the fasteners as suspected had backed off, but that caused a violent back and forth friction between the pressure plate that heated the metal up so much that it actually melted and fused the components together. The fused metal had broken back apart but it was internally rutted/scared such that the pressure plate would not rotate more than 5 degrees and would not separate from the crank despite dozens of hammer blows ….

So I did the unthinkable and I took my die grinder with a cutoff wheel and I sliced thru the ¼” thick pressure plate from bolt hole to bolt hole, and yes I could not completely avoid cutting into the crank face in a few places and then I was able to rip it off, then I cut thru the remaining ring at one location and spread it apart and pulled it off. The crank snout was a bit ripped up and so were some spots around the bolt holes but in general it was fixable with the die grinder and a flat file to get the surfaces level and smooth again. True, there are a few uglies but I am quite confident that I don’t need to remove the crank and re-weld and machine it. I’ll put the new pressure plate on and use a run-out dial micrometer to verify that it is true before continuing to assemble the rest of the transmission.

And yes, the high performance clutch friction plate was worn out already so that limited drag strip time was very very hard on the clutch. Josh and I texted about this and it turned out he had a Kennedy clutch assembly on hand that he will ship to me. It has about 20% more holding power than mine so that should be a good upgrade. I won’t be slipping the clutch at the strip if I go back and I will learn proper heal and toeing for the circuit and won’t abuse the clutch any more. And I have already reset the rpm limiter to 7600rpm, down from 8300rpm.

So I think the clutch pressure plate failure caused all the other failures – setting up the engine for extreme vibration, causing the pulleys to back off as well. Ouch!) - August 31, 2017

 

Part 157 (Josh Arnold, my engine builder, came to my rescue by rush shipping his personal clutch assembly to me. I installed it today, put everything together carefully using ARP pressure plate fasteners and Locktite 262 thread locker, torqued to 60ft-lbs, checked the runout at the outter most edge of the PP (+/- 0.012") and then bolted the transmission and axles back on, plugged in the wiring harnesses, cables, etc. and then started it up and drove it around Parksville/Qualicomm Beach for 2 hours as the sun was setting. It was bliss. I also installed a USRT clutch cable termination assembly and had some fun testing out the new poly steering rack bushings: yes, they eliminate the rubbery feeling of the stock bushings without adding any addition vibration - I am super happy and think they will make track days much more rewarding - especially with slicks mounted.

FYI, the new pressure plate is about 20% stiffer with more clamping force which is important - it feels grabbier - hopefully it will handle a little nitrous - unlike the prior setup. I also went ahead and ordered a 6 puck sprung racing clutch setup from California Clutch today as I want a backup unit that is even stronger than my newest one. I don't really want more pedal pressure but I'd like to be able to use 80hp of nitrous at the drag strip without frying the clutch.

Re the Kennedy clutch assembly: I sent photos of my old and new assemblies to California Clutch and they laughed and said 'that is our friction disk, not Kennedy's and the older PP unit is a modified Sachs unit. They said Josh had custom ordered some friction disks from them with a hybrid organic compound on one surface and metallic on the order side and no springs. I was going by what Josh said to me, and it was all shipped in a Kennedy box and the back of the PP was indeed stamped 'KEP stage 1'. So it looks like the PP is a KEP unit but not the disk.

It will be interesting to see what California Clutch sends to me ... (the 6 puck sprung unit). I am not really keen to pull the trans out any time soon but if I have any more issues with my new clutch I will not hesitate to swap in the 6 puck unit since I have all of the necessary equipment now (engine support, trans hoist, experience, etc).

When I re-installed the transmission I used the USRT clutch cable termination block - a much nicer solution than the OEM h/w.

I also had the chance to check out the HD poly steering rack bushings - they are awesome: no increase in road vibration but all of the rubbery feel is now gone from the steering and that all-important initial turn-in is crisp/precise now) - September 8, 2017

 

Part 158 (I had a chance to get over to the island and prep the car for the required safety inspection at the local BMW dealership that is owned by the same group that owns the track and, yes, I passed the inspection. It was nice that the service technician was a former VW mk1 racer who really understood what this project is all about. I got to the track and mounted the Hoosier slicks and then took it for a slow lap to see if there were any issues: the 1st corner told me that there was some rubbing of the slicks on the rear fender wells so I am ordering another set of H&R race springs and will not cut them this time - that should give me 1/2" of additional ride height, plus I'll move the rear spring perch up another 1/2" which is where there is the most suspension movement (I'd like to go with rear springs that are 20% stiffer as the car still under-steers a bit at the track but I don't have a source). I drove the car home on the slicks just to get more 'seat time' with them and found that they really transformed the steering response - perhaps too immediate with the short wheel base. At 120kmh a 1" steering change results in a pretty fast lane change. I will just have to get used to it. The street tires will never feel as good now.

Update: I ordered the Ground Control coil-over adapter kit with 430/350lbs/in F/R springs after discussing my needs with them. They could not tell me what the H&R race spring rates are but felt that for a car that will see track days and will be using my 28mm rear bar and no front bar, the 430/350 combination would be a good starting point. They offer springs at 50lbs/in increments so I can make future changes - including going softer in the future when I retire the car to be street use only in a year or two. I like the ability to quickly adjust ride height too. They made an observation re. the H&R race springs which have many 'dead' coils and only a short active spring compression distance: weekend track day H&R race spring users complain of coil binding and the non-linearity that results - the springs can 'bottom out'. The GC springs are linear w/o dead coils so will have more potential range of motion. Finally, I ordered Lella 10mm rear axles spacers to replace my 15mm spacers to give me more room for the slicks - this in combination with some increase in rear stiffness and a slight increase in ride height and all should be well - rubbing wise ...) - September 20, 2017

 

Part 159 (Rather than playing around more with the H&R race springs I ordered Ground Control Coil-Over Adapters with 7" 430/350 lbs/in front/rear springs which we determined would be a good starting point for more neutral cornering dynamics and fully adjustable ride height at each corner. After installing them it became clear that the 7" front springs were too tall, making the car sit up 1” higher than ideal (I like about a ½” gap at the fenders) so I have ordered another 440 lbs/in 6" set - the rears were fine. The car is now much stiffer in the rear and it makes driving on the street somewhat harsher, but really, it doesn't bother me too much. I'll back off to 300/200 lbs/in when I retire the GTI from the track in a year or so but right now the 430/350 combination along with the Autotech 28mm hollow rear bar is providing very neutral and stable cornering with slicks on the track.

The car is handling superbly now - it is really quite shocking how quickly it goes around the corners without a fuss - just point the car at the apex and the car immediately goes there without tire squeal or understeer. Never in my wildest dreams did I think my GTI would handle this well - it is world class now. My best lap time in the new 718 version of the Porsche Cayman S (0-60mph in 3.6s and 1/4 mile in 12.0s @ 120mph) using Continental's best street performance tires was a 1:33s time, while I managed a 1:31s time in the GTI while keeping the rpm well below 7000 for 95% of my shifts (average of only 3400rpm) and coasting around many of the corners, soft braking into the corners, having relatively cold tires (the air temp was around 16 degrees C but the track surface was colder as the overnight temps were only 7 degrees C), etc. I am confident that I'll get the GTI into the 1:25s range in the spring when my ride height is down another 1" and the track and tires will be at optimum temps - and when my driving skills and experience on the track have also improved considerably (like learning how to heal and toe properly with my modified wider and longer gas pedal).

One problem I did have was that after the 3rd set of laps on the track I puked up a lot of oil which came out the PCV breather filter and splattered all over the drivers side of the engine bay making a big mess and likely getting some oil on the track surface as well, which is totally uncool. We inspected the track and couldn't see any oil so didn't shut down the track but I felt bad about it and need to solve this problem (oil sloshing forward under heavy braking with slicks and getting out the PCV port at the front of the ABA block) so I have accepted a generous offer from Mike Fopeano, a fellow VW Vortex member, and Mk2 owner/enthusiast, and purchased his mint condition INA Engineering racing windage tray oil sump and will also rig up a racing oil catch can/breather system with a sump return line that plumbs into the INA sump with a separate fitting - this return line will be controlled with a ball valve to as to not risk water based contaminants returning to the oil system under normal use, but at the track where larger volumes of oil can splash out and risk trouble the oil will be recycled.

I check the ECU data logger and at no time did I loose oil pressure around the track) - October 7, 2017

 

Part 160 (I finally had the time to travel over to my new GTI guy garage on Vancouver Island and start the process of building a track-ready oiling system that includes an INA oil pan and an external racing oil catch can with return line. It was cold and damp and so I was freezing my ass off but I managed to pull off the OEM oil pan, pump/pickup and windage tray and start the process of fitting the INA pan to the block and clearance the transmission bell housing (which required a lot of work - tisk, tisk, INA, this wasn't even close to fitting out of the box, plus the 2 hard to reach mounting holes next to the transmission were mis-placed and will require slotting). So after a lot of effort I managed to get the INA pan to fit-up to the block and trans and then measured for the custom racing oil catch can.

The idea for the new oiling system is 4 fold: increase the amount of oil from 4.7 to 5.7 quarts, reduce the tendency for oil to slosh away from the oil pump pickup, provide an external catch can that will keep any oil that finds its way out of the PCV port on the front of the block to a 1 quart reservior, and finally, provide a return line to the oil pan via a one-way 'check valve' - so that oil that pumps out of the PCV port can find its way back into the pan - this is a race track system and will not be necessary on the street. I have now ordered the custom catch can and sourced the lines and fittings so once it all arrives I'll be able to assemble it all.

In addition to this oil system track-only upgrade, I sourced a 2 axis accelerometer as my custom 3 axis unit is too noisy and is therefore close to useless, plus I now have my Ground Control 6" 440lbs/in front springs that I will install. After running the car for a while with the 7" springs, the fender gap settled to 1.25" and so I will lower the car all-round to a 0.5" gap - I highly doubt I will have any fender rubbing with the wide Hoosier A7 slicks as the springs are super stiff and there is very little body movement at the moment) - November 17, 2017

 

Part 161 (It has been a long while since I posted a project update. My spouse was diagnosed with an aggressive form of Breast Cancer in late November and we have been in and out of the hospital and cancer agency 100 times since then having tests run, surgery performed, more testing, and now chemo (followed by radiation and more drugs). She is taking the abuse well enough and we are trying our best to keep soldering on with our daily lives but in reality everything has changed for us and we are trying to find a 'new normal' in the madness of it all. Everyone has been really great - we truly feel blessed even though we realize that this is a life threatening disease.

My spouse wants me to find ways to be happy and reduce my stress so my GTI project is there for me and now that we are into a long period of chemo it is a good time to start to move forward again as the winter starts to change into early spring in the pacific northwest - I want to get back to my Vancouver Island guy garage next month and start to put everything back together and get ready for some track time to debug the new oiling system.

I got a custom fabricated 1 quart can made up by www.racecatchcan.com with a 1" NPT intake bung and a -6AN drain that I will mount where my electrical A/C compressor normally sits (I will use the same mounting holes). I need to fabricate the mounting bracket next and then hopefully I can simply get back to the GTI and start to bolt everything up (yes, I'll need to make up some custom length -6AN SS lines to connect the drain thru the 1 way valve and then to the oil pan drain line port).

After some searching and testing I found that I needed to use a very specific type of 1 way 'flapper' valve (Earls P/N 251006ERL) as I needed just the force of gravity to open the valve and let the oil drain back to the pan. Other spring engaged 1 way valves took too much pressure to work in my situation (they are designed for pressurized systems like fuel lines). Lesson learned. I need the 1 way valve to protect the catch can from reverse flow of the oil in case there is any momentary pressure on the oil in the pan from acceleration and/or oil plugging up the PCV port on the front of the block during hard braking - I am not sure I need it but think it is a good precautionary move to make) - January 18, 2018

 

Part 162 (I finished making the racing oil catch can bracket and sourcing the necessary parts to put my racing oil system into the GTI this past week. The temperatures were still cold here in the Pacific Northwest so after a long day in 6 degree C temperatures under the car I was pretty fozen but the job was completed, along with the installation of the new 6" 440lbs/in front springs and lowering the car all round to a 3/4" fender gaps with the slicks on. I had to clearance the transmission bell housing a bit more to gain access to the oil pan bolts next to the transmission (the next time the trans comes out I will clean up the area a bit more as it is still really hard to get those 2 bolts in). I used Toyota oil pan caulking to first adhere the OEM windage tray to the block with the INA oil pan torqued up to hold everything in place, then I pulled the pan off again, installed the oil pump and pickup, applied the next layer of caulking, and put it all together. The racing oil catch can and plumbing all worked out very well, especially considering that I had to guess a bit when fabricating the mounting bracket and designing the lines (being 100kms away in Vancouver at the time). The only tricky part was ensuring that the oil return line and one-way valve didn't rub against either the tranmission linkage or the CV/axles which are only 1cm away ...

After the oiling system was successfully completed, I pulled out and re-installed the oil dip stick tube which was also leaking a bit at the base - again, I used the Toyota oil pan caulking to ensure a good seal. Then I pulled out the front struts and swapped out the 430lbs/in 7" springs for 440lbs/in 6" springs, and then adjusted the ride height all the way around the car for 3/4" fender gaps (the car will likely settle a bit once it has been driven so I guess that it will end up at around 1/2" which I hope will not rub at the track - if it does, it will be a quick adjustmnt to add back the 1/4" or so). Finally, I attempted to perform a camber alignment but ran into the limitations imposed by the wide rims and slicks which limit the amount of negative camber that I can set without risking the tires contacting the struts under cornering loads at the track. With a 1/4" side gap to the strut body I could only get around -1 degree dialed in (while using 5mm wheel spacers which is the max I want to use) so I have sourced very nice CNC'd adjustable camber plates from Silver Project in Poland that mount to the OEM holes. When I get them I'll go back to the GTI and install them, setting the camber to -2.5 degrees, and will also install a new 2-axis accelerometer and then get the car on the road again for some pre-track testing mid April) - March 30, 2018

 

Part 163 (I was able to install the Silver Project camber upper strut bearing plates with the Ground Control upper spring perches by using a thick 1/2" ID steel washer to couple the wide OD of the spring perch to the narrow OD of the spherical bearing surface. The assembly is about 5/16" taller overall so my fenders gaps have now been set all round to 1" - I am more comfortable with the 1" gap than my prior 3/4" gap as the slicks are very wide and I don't want to risk rubbing at speed on the track - the car would look better with 3/4" gaps but I'll save that for the street wheels and tires. With the new camber plates I was able to get 2.0 degrees of negative camber on the fronts. The rears are factory 1.1 degrees negative and I don't think that adding rear camber spacers to bring them to 2 degrees will make much differences as the rear doesn't do as much work (the tires show little wear in comparison to the fronts after 6 laps at the track at speed). It is interesting to note that the adjustable range on each side of the car was different - I measured the squareness of the frame before welding it up and it was straight (even though there had been a relatively minor passenger slide fender bender years ago) - the car drives straight and true with the alignment done so I can't complain.

I used toe-plates and tape measures to get the toe-out to 1/8" - it takes about 1/6th of a turn of the tie-rod ends to get a 1/16" change in toe the way I am measuring it. I was able to use the top edges of the toe-plates to sight the alignment of the front wheels relative to the rears and expected that if I got the steering wheel positioned straight and the front wheels aiming at the same positions left/right on the rear tires, the car should drive dead-nuts straight - and yes, it does!

I was also able to swap out my home-made accelerometer with an after-market unit and reprogrammed the ECU for properly calibrated readings. I will now be able to record my track lap g-forces and see how well the car/driver is performing lap to lap - finding what works and what doesn't work to improve my technique.

My 20 minute road driving test proved that the oil pan gasket area is not leaking - there were some oil drops on the underside of the pan and on the lower stress bar after the test drive but I couldn't not see where they originated from. I had previously sprayed oil all over the engine bay and may not have cleaned it up fully so I will put on the street wheels/tires before going to the track and drive it a lot more, looking for any oil leaks.

It was fun driving the car again as I had forgotten how intense the 2nd gear acceleration is from 4-7,000prm - it is almost too much for a FWD car as any road surface changes can pull the car left or right suddenly. Quite the intense experience.

I also started the process of re-gluing the upper door rubber seals but ran out of time and patience. Those rubber parts do not stick well with Impact Adhesive or 3M window gasket seal so I am using Goof-off to slowly remove the old glue and then will try a different product) - April 24, 2018

 

Part 164 (I installed the Quick Latch hood pins with minimal trouble and I am happy with how they look and function (and most importantly I now have the peace of mind knowing that my expensive carbon fiber hood that I spent 100s of hours on won't blow off at the track if the OEM hood latch pulls out of the carbon hood). I honestly tried to get to the track for the 1st this this year but it was a rain-out, plus I ran out of gas on the highway as I drove towards the track - it seems that either the level sender (which is new) somehow got stuck at the 39% full level, or there is something else wrong - I will pull out the sender next time I am back and if it seems fine and provides full range output to the ECU I will pull out the fuel pump input filter and see if it is partially plugged. Finally, I tried to trace the source for an oil leak at the drivers side rear lip of the new INA oil pan by recording video with a remote camera - the camera did record the oil leak which seems to be coming from a single bolt - I will pull out the bolt and put sealant in the hole and put it back in, plus will look more carefully around the area - it does not look like the gasket itself is leaking - I thought it might be the rear main seal but I see no oil in the area of the transmission bell housing lower lip (I hate oil leaks)) - May 11, 2018

 

Part 165 (After getting most of the oil leaks addressed (there is still a little hunting to get the engine 100% leak free) I got to the track and tested everything out, shooting some interesting video from a camera mount on the outside of the driver side door. The new INA oil pan did its job and kept oil out of the PCV port and therefore the new catch can had no oil in it at the end of the day - at least it is insurance against oiling down the track. I inspected the underside of the car after the drive back up island to Parksville and found that the racing exhaust header collector brace that I had fabricated had cracked so I will bring my TIG welder over next time and get that repaired and strengthened. Next major task is learning to drive the track quickly and practice my shift points and heal-and-toeing technique (my new gas pedal plate works well for side-to-side brake/acceleration movements with my foot but at times during heavy braking my brake pedal is too low to allow easy access to the gas pedal so I may move the brake pedal up 1/2" more to compensate)...) - May 28, 2018

 

Part 166 (I brought my 210amp 240V powered TIG welder over to the island and sourced a 4000W voltage up-converter to allow me to power the unit from a 2200W 120V generator - testing showed that I could weld with up to 80amps of current which was more than enough to patch the stainless 16 gauge header tubes and weld on a new stronger bracket - it all worked out well. I also swapped out the cracked transmission shifter bracket assembly and got everything re-calibrated for nice crisp shifts. I also took the opportunity to hunt for minor oil leaks with the exhaust header out of the way - I was quite sure that oil was leaking from either the head gasket or the exhaust ports and low and behold all of the exhaust valve guides were leaking significant amounts of oil and after checking the intake runners I found minor leaking of the intake valve guides so I spoke with Josh, my engine builder, and he told me that the SuperTech valves he had installed came with special valve stem seals that had caused similar problems with other engine builds he had done the year he did my engine and that simply swapping out the seals for OEM seals solved the problem. I have always wanted to drive the car to Josh and Techtonics in Oregon to let them see and drive the car so I will now do that in September and Josh will also perform a solid lifter valve lash adjustment at the same time which will be good to complete (the last time I checked the lash specs were all in range).

My eldest son Perry was in town this week and he is a car guy too so he agreed to come to the track with me, do some driving and garage pit stop wrenching for me so the day at the track was more fun and entertaining than usual. He had the chance to drive a 2 series BMW and when I drove him around he was quick to state that my GTI felt way faster down the straights and in the corners - which is true but it is nice to see someone go back-to-back and experience the differences. I mounted the camera a bit lower down on the outside of the door to try and catch a view of the front tires moving in relation to the track/car direction and it sort of worked. I have now eaten through my rotors with the Hawk DTC-60 race pads which are quite dusty and very agressive/hard on the rotors. They really increase the brake stopping torque on the the rotors at the expense of eating them alive - I probably should have replaced them last time I was at the track as they are way past the normal wear limits after yesterday's track session.

When I put the exhaust header back on the engine I used Locktite Ultra Copper gasket sealant which has kept the oil from leaking out onto the back side of the engine. My oil leaks are now pretty much killed off and I am now happy about that. Next time I get to the track I will change over to fully synthetic oil now that I have over 2,500kms on the engine with several hours of racing on it as well and I will put new rotors and pads on the front disks. I have been adjusting the brake proportioning valve to slowly increase the rear brake pressures on the track and managed to get the car sideways on the track for a bit yesterday so will back it off a full turn. Finally, now that the car is becoming reliable on the track I will settle into learning how to drive it quickly - the proper line, maximum rpms, deepest/hardest braking efforts, best shifting strategy, improved heal-and-toe technique, etc. I think the GTI is capable of some very quick lap times, much quicker than most high performance street cars that visit the track - but it will take a full season of practice for me to prove that out) - June 14, 2018

 

Part 167 (The old rotors were down to 18mm (from 20mm) and had at least 1 stress crack out to the edge from one of the drilled holes. I will switch to non-drilled rotors next time but this time I have put in higher quality drilled and slotted rotors and will just keep a close eye on them and swap them out a bit earlier. They look like they are mounted backwards but that is the noted direction of rotation stamped on the hubs ... must relate to the direction of the internal vanes.

My one-off new front upper spring perches worked out as well - no more noises.

I finally switched to synthetic oil at the 2700kms point - the engine now runs smoother/quieter.

I got some track time with an instructor and shaved over a second off my prior best time: 1:31.33 now. On the hunt for a sub 1:30:00 time now. By reference Kees Nierop, a Porsche factory race driver, was able to lap a 718 Cayman S at 1:28 on OEM tires and 1:24 on slicks. I have lots of room for further improvements and hope to see a 1:28 or 1:29 eventually. Kees would be able to shave a few more seconds off of my best time ... ) - July 6, 2018

 

Part 168 (I brought Kees Nierop, a former Porsche Factory race driver and instructor (winner of 12hrs of Sebring, factory driver at Le Mans), to the Vancouver Island Motorsports Circuit to try his hand at putting down some hot laps in my GTI. The day was hot and sunny with air temperatures of 33 degrees C and track surface temperatures of 45 degrees C, which was not ideal (about 6% down on power, plus the GTI was wearing Hoosier A7s which are cool temperature tires - a better choice would have been R7s which would provide better grip all round on a hot track day). Kees settled into the little GTI and immediately found that the steering wheel on the Mk1 Golf isn't adjustable but went ahead and made the best of the fixed driving position.

After some warm up laps he knocked off 3 back to back 1:26s laps (with one of the laps showing a 1:25.48 on Harry's Lap Timer with an external high frequency GPS unit). My prior best time was a 1:31.35 in cooler temperatures so it shows just how much better Kees is at navigating his way around the track even though this isn't a car that he is used to driving. I had the nitrous bottle ready to go but the temperatures were too high and we felt the tires wouldn't hold the added power so it will have to wait to another day. Kees feels that he can improve another 1-2 seconds without the nitrous.

A major reason for building the little GTI was to prove that simplicity and light weight are lost concepts that need to be re-discovered. I wanted to build a Mk1 Golf that would compete head to head with the best of today's sports cars and certainly beat any of the current model Golf cars available for sale today. Without the nitrous the GTI is already putting to shame various 911 and Cayman performance edition models on the track, and with the nitrous and better traction from R7 tires and cooler temperatures this little car is likely capable of running with track-day oriented Porsche models. I am blown away by how much performance Kees was able to demonstrate - it makes this project so satisfying. Here are Kees' notes after driving the GTI:

Doing three laps within .3 sec. is a good thing as it shows "comfort" and predictability.

Yes, I can go faster. But I like to work on keeping "brain power" available while going fast, so I can explain what the car is doing or not.

I like the little car. Once you settle in it is fine! The one thing it could use is a more proper driving position with the steering wheel. With all the work being done by the front wheels, it is important to have full control and full arm strength while holding on to the wheel. An adjustable steering column would fix that.

The car felt stable enough at full throttle thru Turn 1, I tried shifting before, during and after. The car didn't upset that much when the drive line power was interrupted.

at T2 the brakes would actually help rotate the car a bit and then by immediately getting on the power it would "pull" itself around T2. I was able to get early power on.

T3 - This is a turn I always respect.....I like to go in deep and then hard brakes and have a "low" speed at the curb on the left. That is where I set my attack for the rest of the turns T4-T5 -T6. The car turned in great and never displayed any under steer. Able to short shift between T5-T6 and full throttle out of T6.

T7 is the downhill left. Straight forward 90 degree ...... just needed to be careful with the brakes, but the car felt neutral.

T9-T10 was a little bit of an eye opener......The quick left - straight - brake - right - lose gravity - left - full throttle - was a handful for the car.  This is where the short wheel base made the car "twitchy". Again no real surprises so all good.

T11 is all about wheel spin and again at T12....wheel spin.

T17-18-19 is a bit like T9-T10. Very quick direction change and short wheel base. This is where a very comfortable seating position and steering wheel position become very important.

T19 (onto pit straight) is a drop. The suspension is being used to it's fullest extend and something touches a "stop" (helper springs likely required with the short/stiff ground control springs)

 

All in all, I feel I got into it a little and am pleased with how it behaved. We can squeeze a high 1.24 or low 1.25 next time?

- August 8, 2018

 

Part 169 (selling off the race only GTI components) - September, 2018

 

Part 170 (The long road home - right from the beginning of this project I had always intended to put some track time on the car to help wring out its full performance potential. Yes, extensive track time put stresses on the car and uncovered many small and large issues with the various systems, but it all served to harden up the design and make it much more reliable. And most importantly it showed that a 40 year old Mk1 GTI design, with the help from some tweaks here and there, could produce a car that not only exceeds the performance envelope of a Mk7 GTI or R spec golf, but also exceeds that of a Porsche 718 Cayman S. That is truly incredible stuff, confirming the initial project thesis that yester-year concepts of "small", "light", "simple", and "manual" (no power steering, no ABS, no stability control, etc.) could indeed produce a car of modern world class performance potential.

Kees Nierop, a former Porsche factory race driver, after experiencing the car on the track, said my GTI had strong brakes, excellent turn-in and neutral cornering manners, and a great engine that pulls strongly out of the corners and down the straights. He said the short wheelbase makes the car feel more nervous in the S curves than a modern car, but he feels the GTI offers an overall more immediate, real immersive driving experience, making it much more of a drivers car.

After Kees completed his track testing of the GTI, it was time to get this project properly completed, putting it fully back into a street car form, complete with its original interior and a more suitable street performance suspension and brake setup - performance oriented but liveable as a daily driver, complete with electrical AC and a great audio system and a long 5th gear for comfortable highway cruising speeds.

So far I have pulled out the front suspension, control arms, axles, brakes, cylinder head and pistons, and have cleaned up the heads. I have new piston rings on order along with new valve stem seals for the head which should all arrive by end of January. In the mean time I will pull out the radiator and transmission and start on the 5th gear swap from the 0.91 to 0.76 ratio for improved highway cruising rpms) - January 3, 2019

 

Part 171 (My apologies for the delay in posting this update. I have actually been very committed to the project over the past 6 weeks and have an unusually long update to share. The cylinder heads and block have been totally rebuilt, the transmission now has a new 5th gear ratio, and new suspension springs have been selected and ordered after testing the Eibach race springs.

This was my first time tearing down and re-building a 16V motor and so I made a fair number of 'newbee' mistakes. Let's start with the cylinder heads: I have 288 solid lifter race cams, VR6 tall HD valve springs and narrow 5.5mm intake valve stems so there are a lot of custom parts and unique things to juggle. The 288 cams are high lift so it is harder than normal to take them in and out as the cam journal cap bolts won't start without careful positioning of the cams - each one needs to be at a different location to minimize the lift so the right technique is to do one at a time and not try to position them both at once to torque the caps down. I didn't realize that 288 race cams are hard on springs and even if they test out OK, pressure wise, they can crack/fail at any time so should be replaced every 2-3 years. I also didn't realize that valve stem protectors need to be used to avoid ripping the delicate edges of new valve stem seals - so the valves need to be installed before the seals go on and then they cannot be removed again. Then I also fought with the valve lash settings, replacing lash caps multiple times to get to the ideal 0.015" exhaust and 0.010" intake specs. And Techtonics saved the day by custom grinding 5.5mm caps for me when I couldn't find them anywhere in stock plus they were able to help me get the VR6 HD springs setup correctly (installed height and pressure). It was more effort and a steeper learning curve by far than I expected but I figured it out. Amazingly I forgot that I once the cams are installed the intake valves start to stick out below the deck height and I almost bent some valves before I got a wood spacer under the head to protect the valves - a seniors moment for me I guess. I filled the intake and exhaust ports with alcohol and checked for leaks - and I am lucky there are none so we are good to go now with the head fully re-assembled and the intake ITB system re-installed as well.

The block was another learning curve as I ran into fastener hell a few times: OEM VW crank main bearing caps are single-use stretch bolts that needed to be ordered, but I have ARP rod bolts which are fine for re-use; the crank sprocket was a custom item that was based on a 16V sprocket (BBM makes them - p/n 027 105 263 B) but needed to be machined to accept the larger 16mm crank bolt required for the late model 95.5mm stroker crank) and a special ARP fastener sourced (Integrated Engineering worked with ARP to design this bolt for the stroker crank, M16x65mm, available from ECS Tuning p/n 2794733 - but I needed to machine off 1-2mm to keep it from bottoming out), plus the highly recommended hardened steel dowel pins needed new holes drilled in precisely the right locations to match up with the crank holes (Integrated Engineering sells a dowel pin installation kit - note, I ended up sourcing 1" long 3/16" dia hardened dowel pins and didn't use the 3/4" long pins as they can back out of the crank holes as they are too short in my view). I had damaged my timing sprocket from high rpm vibration so it was a very tricky operation to drill through the old sprocket dowel pin holes and create identical holes in the new sprocket - in the end I had to open them up about 0.010" to get alignment with the crank holes but the sprocket is perfectly located and secured now with its massive 78 ft/lbs + 1/4 turn torque spec. I used a flex-hone to prepare the cylinder walls - it worked out very nicely. I ordered new Weisco piston rings and installed them with new ring pliers. I had the crank serviced at a local crank shop that made sure the damage from the high rpm vibration on both ends of the crank was addressed with clean-up machining, and the bearing surfaces were also re-polished. The crank, rods and pistons were all re-assembled and torqued, and then a new VW ABA windage tray was installed with the oil pan using Reinzoil gasket sealant (I am tired of leaky oil pans).

I worked with Broke-VW to get a 0.76 5th gear and all of the tools and gaskets and replacement single-use bolts and clips to swap out the shorter 5th gear - it worked out well but the process was challenging for me - lots of learning going on when transmissions are involved - harder than working on a cylinder head in some ways. I was swapping an 8V 5th gear into a 16V transmission so I had to do some machining on the 8V gear to get the securing clip to fit correctly - with help from Broke-VW.

I wanted to test the Eibach race springs that I had originally used on the car before swapping in the coil-over Ground Control springs/adjustable perches for racing purposes - on the track I needed to run 440lbs/in front and 350 lbs/in rear springs to get flat and neutral cornering but those are way too stiff for a daily driver on the street. I found the original Eibach race springs pretty decent on the street but felt that going about 25% softer would be a nice compromise for me - still pretty performance oriented but just a bit less edgy. So I needed to measure those springs as there is no published data on them. I used a weigh-scale platform and a car jack to build a test rig. The results (drum roll please ...): to collapse the front dead coils takes 300lbs, and then the spring is 300lbs/in after that; on the rears it is 250lbs to collapse the dead coils and then 250lbs/in after that. So they are pretty stout. I have now ordered 250lbs/in and 200lbs/in front/rear Eibach coil-over springs to install with my Ground Control adjustable spring perches.

I also machined and welded up a new oil pump priming tool and got my exhaust header re-welded with a much stronger support bracket. In-between waiting for out-sourced machining operations and parts to arrive I also re-epoxy painted many engine and suspension components and continued the task of cleaning up the body, pulling off the fender flares and prepping them for re-plastic painting as they are already a bit worn looking. The project is starting to heat up just as this long winter in the Pacific North-West is finally starting to ease its grip on us - I estimate later in April or early May for 1st drive) - March 13, 2019

 

Part 172 (Success! The California Clutch stage 5 clutch and pressure plate assembly was balanced and then installed on the engine, the transmission with it’s new 0.76:1 5th gear set was bolted on, and the combined assembly was lifted into place and bolted back into the chassis using slightly modified BlackForest Industries engine/trans mounts. Then the custom radiator was installed, the rebuilt cylinder heads, and finally all of the sensors and lines and exhaust system ... after priming the oiling system with my custom drill mounted oil pump drive I fired it up 3 times, each time increasing the max temp from 120 degrees F, to 140 then to 175 degrees, with a full cool-down between runs. The plugs were pulled and inspected and they were 'as new'/shiny.

Leakdown tests were performed after assembly (5-9%), after the oil priming and starter driven cycling (5-7%), and after all 3 test fires – a total of 10 minutes of run time (3.5-4.5%). So the engine is working really well: no blue smoke, no smell, no fouling, no oil leaks, all good!

I installed a USRT shifter linkage system and test fitted a SCCH shifter (since removed and sent back to Jacob to hopefully get it to feel less stiff). I also got the fender flares repaired and re-painted with plastic paint and then a top coat of plasti-dip satin black which looks really nice. Finally, I machined down the front strut bearing inner sleeves to reduce the slack in the bearing but leaving what I hope is enough tolerance for the control arm movement) - April 8, 2019

 

Part 173 (After getting the OEM interior back in the car and doing a careful alignment (using strings, tape measures and a digital level - old school, baby) it was time to take the car on the road. 100+kms into breaking this new engine in I can say that it is amazing. Here are my main points:

Not too stiff so the car manages to get over most road bumps with grace and a smooth, comfortable ride (using 250/200 lbs/in front/rear springs and Bilstein race struts and a large hollow rear bar - even though these springs are close to the 300/250 springs I originally had in before racing, going one step softer was a smart decision). It still corners dead flat and has very responsive slalom/lane change manners - go-kart level feel in comparison to most heavier sports cars.

Sticking with the OEM front upper strut mounts and adding rubber sealant to them is another nice addition - no crashing, no harshness. 3/4" wheel to fender gaps all round now that the car has settled in a bit.

The alignment is also sweet: -1.25 degrees camber, 1/16" toe out, 5mm front wheel spacers, 20mm rear axles spacers + 3mm wheel spacers - gives a more aggressive stance, evens out the front/rear wheel width - car steers dead-nuts straight.

Adding some mass loaded vinyl to the trunk area and putting in the carpet, plus adding some material to the door seals at the front edges made the car much quieter.

Add the 0.76 5th gear and this car is now a dream on the highway, turning 2000rpm at 50mph and 2400rpm at 60mph - no more droning.

The seats feel wonderful, the USRT/SCCH shifter is amazing too. I couldn't be happier. After this tank of fuel is gone I will change the oil again and then start to use the full rpm range and do some full power hill climbs to complete the engine break-in) - May 1, 2019

 

Part 174 (Finally the Ultimate 83 GTI project is complete as a street car/daily driver. No fluid leaks anywhere, a/c system running well with a 12 degree C air temperature drop across the new evaporator (and with the help of a new larger condenser), all final 'fit and finish' tasks completed, and a 500kms 'shakedown drive' in 33 degree C heat to confirm all systems 'go'. I will now repeat my 1984 drive from Vancouver to San Francisco along hwy 1 in the next few weeks in my new GTI. I am arranging for a pro video and online spec sheet/review to be made of the car as the final step in documenting this project) - June 15, 2019

 

Part 175 (I have been taking people out for rides and part of the fun is doing some full throttle acceleration runs to show off the brutal acceleration potential of this car - when the cams hit their sweet spot between 5000 and 8000rpm things get more than just a little crazy with this 1900lbs FWD short wheel base car. But as I progressively did more acceleration runs I noticed that the transmission was getting harder to shift and there were strange noises coming from it when feathering the throttle - like marbles rolling around inside it or growling. So I drained the trans fluid and saw lots of silver flecks in the oil - a bad sign. I then spoke with Brian of Broke VW fame who has been so helpful to so many people in the VW 020 transmission world, who got me my 5th gear conversion setup and he suggested that it was indeed time to rebuild the transmission.

I called Ken Harvey at German Transaxle of America (in beautiful Bend, OR) where I originally sourced this 020 2Y (16V mk2) transmission from, and he said 'yes, I can rebuild it but I am leaving for vacation at the end of this week - when can you get it here?' so I ran into the garage and spent the next 3 hours pulling the transmission out of the car, throwing it into the back of my Audi A3 Etron and driving thru the night to get to Bend, OR by 8am the next morning. Ken gave me a wonderful tour of GTA which is definitely THE BEST VW transmission shop in America with its huge hard to find parts inventory and extensive rebuilding and testing capabilities. Ken got his team to work tearing it down immediately, getting the parts into the washer, repainting the case, and then completing an inspection of all of the internals. He found a badly damaged ring and pinion gear set and lots of worn synchros plus some worn bearings so all bearings and synchros were replaced, new R&P gearset installed, and some other items as well. It is now on its way back to me via UPS 2nd day air so I can get it re-installed in the car next week and then hopefully get on my way to San Francisco mid month - weather depending.

The bottom line in all of this is that I was using a transmission that was designed for 100ft-lbs of torque and running 200-250ft-lbs thru it at 50% higher rpm than spec on the race track, at the 1/4 mile strip, with slicks, power shifting, etc. - it lasted 4000kms which is actually quite good all considering. From now on it will be babied at lot more ...) - June 27, 2019

 

Part 176 - (4,000km/2,500mile road trip: I wanted to relive my original summer 1984 GTI trip from Vancouver, BC to San Francisco down the coast, to bookend my Ultimate 83 GTI project after a nearly 7 year journey. Would it survive the trip without mechanical or electrical troubles, and what would it be like to drive it for 40+ hours on a range of roads across the Western US. The short answer is that the only mechanical issue was a disintegrating exhaust system flex pipe which I had replaced on my last day of the trip in Yakama, WA, and there were no electrical issues.

The GTI handled the trip very well, except in the few areas where the pavement was rough - my suspension tune is still very firm - it works wonderfully on smooth roads but later this summer I will be receiving my KW V3 coil-overs and will incorporate my 250/200lbs-in springs into them and achieve more compliance for street-only GTI driving. The GTI has the 16V 3.67 final drive ratio, and I had swapped in an 8V 0.76 5th gear so my cruising rpms were low enough to enjoy 75-80mph speeds for long periods of time. At times the exhaust system noise level was a bit tiring - since coming back from this trip I swapped in the Techtonics high flow catalytic converter - it has maybe cost some power but the exhaust note is much more mellow now and over-all part throttle volume is about 1/2 so hwy cruising is now awesome. Once I have the KWs installed the GTI will be a very street-friendly car indeed.

I visited several project supporters along the route: Josh & Mark Arnold, Collin Gyenes & team at Techtonics, Tim Linerud, Derrick Hoffman, my son Perry who lives in SF, and the team at German Transaxle. Thank you to everyone for their hospitality and support!!!

My trip route was Vancouver to Portland via I-5, then out to the coast on 99-W, and then US-101 all the way to San Francisco, and then back up to Sonoma and then out to US-1 on the coast, then back to SF on US-101 again, then south on I-280 and across I-92, then I-580/I-680/I-80 to I-5 to Mount Shasta, then I-97 to Klamath Falls/Crater Lake, then continuing on US-97 to Yakama, then I-90 back to Seattle and then I-405/I-5 home to Vancouver again in a 6 day period. Peak elevation reached was over 8,000' at Crater Lake and another 4-5 passes in the 4-5,000' elevation levels - lots of varied roads and scenery to enjoy and test out the GTI with.

Catalytic Converter update: before the Cat installation the car always had a rich smelling exhaust even though the WBO2 sensor and ECU were in closed loop mode and regulating to 14.7:1 A/F ratio. After the cat installation but before ECU tuning the exhaust smelled of rotten eggs and the cat was a bit too hot for my liking (at 350 deg F inlet flange, and 650 deg F outlet). I googled around and found out that racing cams with a lot of intake/exhaust valve overlap pull air thru the cylinder head into the exhaust creating an artificially lean signal to the WBO2 sensor and also that the signal is noisy so you can't leave the ECU in closed-loop mode at idle with racing cams, but instead should solely tune based on max intake vacuum and idle quality/stability. When I did this I ended up with an indicated 17:1 A/R signal at idle and no more rotten eggs so my car had indeed been running rich at idle all this time (8,000kms). My plugs were rusty brown looking too so that was the issue after all. The cat outlet temp fell by 75-100 deg F as well which indicates that it is not having to work as hard. I also changed the injectors 'end angle' from 0 to 30 degrees BTC so that less raw fuel is likely to sneak thru the intake to exhaust system before the valves all close and the compression stroke completes. Another ECU programming change I did was to hold the A/F to 14.7:1 until the MAP signal indicates full throttle so the engine doesn't run rich when accelerating at part throttle any longer. Finally, I fully programmed the deceleration fuel curves to lean out the engine when off the throttle during compression braking - this gives an average A/F during decel of 16-20:1 which is OK as there is no lean back-firing or instability indicated . So the GTI is now quiet, smooth, and doesn't smell of a rich exhaust or rotten eggs which is all great news.

Notes: A/F = air fuel ratio; WBO2 - wide band O2 sensor, ECU - engine computing unit, MAP - manifold absolute pressure (vacuum), at 14.7:1 A/F in theory all fuel burns to create nothing but CO2 and water vapour - but in practice also produces CO and unburnt HC (hydrocarbons) which the cat cleans up, rotten egg smell is the result of sulfur in the gasoline combining with hydrogen in the cat to create hydrogen-sulfide (and also typically indicates a rich A/F condition, max cat inlet to outlet temp difference should be under 300 deg F - it is actually burning/converting the pollution and in the process is heating up the exhaust gas significantly so the whole exhaust system post cat will be much hotter the without a cat in the system (you will need to add thermal insulation to keep the heat away from the body of your car as well as any wiring and fuel/brake lines, etc.) - July 16, 2019

 

Part 177 - (This is an informal chat about my views and experiences driving both my Mk1 Ultimate 1983 GTI and my 2018 Audi A3 Etron (based on the Mk7 Golf platform) as well as highlighting some of the spec differences with the Mk7 GTI. Summary: I love them both and think they each have their strengths - but there are blissful moments in the Mk1 GTI with its huge performance envelope and immediate/mechanical driving experience that clearly come out on top: when the driving conditions are optimal the Mk1 GTI shines brighter than more modern cars do. But in average conditions a Mk7 would be more comfortable, quiet, smooth, and often quicker given the transmission and suspension designs - and certainly lower stress on average. On the track there is no question that the Ultimate 83 GTI would dominate both the track times and the driving experience in comparison to a Mk7 GTI or R spec car, and it can also exceed that of a Porsche Cayman S or BMW M2/M3 but there aren't often driving conditions that parallel track conditions. Of course, safety is a big features of modern cars and the Mk1 lacks many of the basics there ... something to keep in mind when going 10/10th in an early car) - July 18, 2019

 

Part 178 - (I used my ECU self-tuned fuel table to calculate the torque and HP curves for both my non-Cat and Cat equipped exhaust systems. Previously I had performed multiple dyno tests on the engine, determining that the best results were obtained without the intake ITB air box or filter, 32 degrees of total timing and a 13.2:1 air/fuel ratio, achieving 205hp at the wheels, which translates to around 240-250hp at the crankshaft. Adding the air box and filter cut about 10hp due to impairment of the ITB trumpet air flow characteristics.

I used 0.42lbs/hp-hr BSFC (brake specific fuel consumption) which agrees with my dyno test results and is inline with what race-prepped normally aspirated engines would see, vs 0.47-0.50 for a garden variety OEM engine.

The results were that the non-cat engine with the air box and filter registered 235hp and 180ft-lbs while the cat-equipped engine registered 218hp and 160ft-lbs of torque, but the real story is in the shape of the torque curves: the cat-equipped engine produces up to 40% more torque below 2000rpm and 11% more on average below 4500rpm where the majority of street driving occurs and only loses 7% on average above 4500rpm, and it has the effect of flattening out the torque curve so that it is almost level from 2500-7500rpm - making the engine feel very smooth and willing to rev over its complete rpm range.

On the track it makes sense to remove the air box and the cat and let the engine rip, but on the street it is far more enjoyable to have a car that is relatively quiet, smooth and tractable at all revs - without a fuel-rich smelly exhaust! I am very happy with the results.

As a background matter, running a cat with 288 race cams required leaning out the idle somewhat as well as backing off the timing at idle, plus reprogramming the fuel map to kill all fuel during deceleration - August 3, 2019

 

Part 179 - (After a 9 week lead time wait my KW Variant 3 p/n 35280001 dual-adjustable struts and shocks arrived from Germany (these days no-one stocks mk1 KW V3 kits so they are 'made to order' at the factory and drop-shipped). And it was well worth the wait indeed - what beautiful components these are, made of stainless steel and polymer materials. And not only are they compression and rebound adjustable over a wide range, but the compression system is a dual valve design that bypasses the adjustable valve when the car hits a rough bump, letting the strut/shock move to absorb the bump without upsetting the car while using the more restrictive adjustable valve for control over normal road surfaces - making the system much more 'street friendly'.

The V3 kit comes with 342lbs/in front and 285lbs/in rear springs with additional 'tender' springs that are meant to keep the springs under slight compression when the wheels are fully unloaded. The problem with 342/285 springs for a mk1 VW is that they are a bit too soft on the track and a bit too stiff on the street. A great track setup is around 400-500lbs/in front and 300-400lbs/in rear (with a big rear sway bar) for a 2000lbs mk1 VW and a tolerable street setup is around 250/200 - many people run stiffer than that on the street BUT they put up with a lot of crashing over rough pavement - trust me, I have driven almost 10,000kms on 300/250 springs with seriously stiff racing Bilstein struts/shocks and they don't suit themselves to about 50% of the roads out there in the real world.

So I swapped in my newer Eibach 7"/8" 250/200 springs (2.5" ID) for the KW 342/285 springs and dialed back the compression/rebound to 1 click off 'full soft' and the KW V3s became truly transformative. All of the banging and crashing over rough surfaces was gone and in its place is a supple ride that is still quite sporty, limiting body roll to a few degrees when yanking the wheel back and forth (let's call this 'drive with spouse' setting). Steering feels lighter at center, the car feels calmer and more confident, and it still has very good turn-in and dynamic movement control. I next dialed back in more compression/rebound stiffness: +2 clicks is more sporty without harshness (will be my default setting for daily use), +3 clicks starts to get into the harsh mode but still acceptable for general performance use (my boy-racer mode), +4-5 clicks starts to enter into the prior Bilstein zone - very stiif and not very street triendly (track use ...). Now I realize how stiff my Bilstein p/n V36-0059 rally race front struts really were - they are perfect on the track with 440lbs/in springs but are too much for me on the street) - August 26, 2019

 

Part 180 - (Selling off the remaining Midnight Blue Seat Fabric)

 

Part 181 - (Complete Project Review & Walk-Around Inspection)

Media coverage on this car: VW Newsroom, Automobile Magazine, Motor Trend Magazine, Classic Cars Journal, CarBuzz, Auto Blog, Yahoo Entertainment, MSN, Motor 1, AutoWeek, Car & Driver Magazine, Classic Cars, Hagerty, Hemmings, Top Gear, The Drive, and many more international web sites. Amazing. Thank you everyone!

This video is also available in a PDF formatted long form (125 page) document and separate hi res photos are also linked from here: http://derekspratt.com/HTML/Automotiv...

This video is a complete step by step review of the project and towards the end has a walk-around detailed inspection of the car:

Ultimate 83 GTI Specifications Summary:

• US$140,000 invested plus thousands of hours of time
• 1800lbs in track trim, 1950lbs in street trim (with some options removed)
• 240hp from 7,250-8,000rpm w/o catalyst or air box, 220hp from 7,000-7,400rpm with catalyst, air box and filter
• Up to +100hp with progressive ECU controlled nitrous system
• Hidden chassis frame and stiffening throughout
• Carbon fiber hood, hatch and bumpers, Lexan rear window
• Epoxy primer ... wet sanded glossy clearcoat
• New OEM interior throughout – gorgeous NOS seat fabric, new firm foam
• Mk3 ABA block, Mk2 16V heads, 288 solid lifter cams, oversized 34/29.5mm valves
• 95.5mm stroker crank, 11.5:1 83.5mm pistons (2092cc)
• Custom curved ITB intake, Lexan air box, with dual fuel rails
• Stainless steel braided hoses with race spec AN fittings used throughout
• 1.75” primaries stainless steel race header, 2.25” stainless steel exhaust, 2.50” tip
• Custom built VW 020 5 speed close ratio transmission with Quaife LSD, 100mm flanges
• Stage 3 and stage 5 clutch systems (stage 5 currently installed)
• 500hp rated race axles • Custom radiator, electric water pump/controller
• Custom oiling system with external filter and oil intercooler
• 25Amp-Hour 13.5V Lithium battery system, computer controlled alternator charging
• Holley Dominator ECU with 150 inputs/outputs
• Holley touch screen digital dash, Holley individual coil race ignition
• Wilwood/Tech-53 big 4 piston calipers, 10” rotors, Hawk pads, adjustable proportioning valve, rear disks, ECU controlled servo vacuum – console adjustable
• KW V3 stainless steel struts/shocks compression/rebound adjustable in 16 steps, multiple spring sets for street and track use
• Hollow rear 28mm sway bar
• Urethane and Delrin bushings used throughout suspension and steering system
• Special shift linkage – ultra precise shifting
• Leather wrapped OEM steering wheel, custom steering column & u-joints
• Quaife close-ratio rack & pinion - blissful steering precision & feel
• Brand new sunroof mechanism
• Electric windows, seat heaters, Air conditioning system
• 1200W Bluetooth audio system
• Philips LED headlights, LED bulbs used throughout
• Looks dead stock inside and out but outperforms a Porsche 718 Cayman S on the track

- December 1, 2019

 

Part 182 - (Project Recap, Media Coverage, what's up next: e-minibikes: In this video I pay my respects to the international VW community that supported me during this crazy project. I explain why I spent approximately US$200,000 total on this project - no, I am not crazy, I wanted to do something special to honor this great little car. I also go into the background as to why VW chose to put out a press release on this car as well as touch on some of the reasons why I did this project and what it meant to me. Finally I talk about what is coming up next: e-minibikes. And then eventually an electric 1961 Beetle) - March 14, 2020

 

 

Index of Project web pages:

Project Overview, Goals & Specs

The Ultimate 83 GTI Summary

Project Car Initial Condition
Chassis Development
Bodywork & Paint
Suspension, Steering & Braking Systems
Engine, Oiling, Cooling, Transmission & Exhaust Systems
Electrical, A/C & Fuel Systems
Interior
Performance Validation
Final Street Trim Conversion

VW Vortex thread on this project

Videos # 001 - 049 (Feb 2013 - May 2014)
Videos # 050 - 099 (Jul 2014 - Sept 2015)
Videos # 100 - 149 (Sept 2015 - May 2017)
Videos # 150 - 181 (May 2017 - Dec 2019)

My original 1983 Rabbit GTI (owned 1983-1987)

Exit to Home Page