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VWVortex.com Miscellaneous Features I hope you’re ready for a really sad story… However, before you reach for that box of Kleenex, rest assured that there is a happy ending. This installment of the Rally VRT project is financially and emotionally painful for me, but will hopefully be a major learning experience for everyone who follows this series. It involves impatience, excitement, and reckless abandon. I have witnessed these attributes destroy many projects before they even have a chance to develop, and now, I have fallen victim to them as well.
After a weekend of babying the Rallye around the no-left-turn-and-can’t-pump-your-own-damn-gas state, and collecting a moving violation from a “nice” officer in East Brunswick, we were able to hook up with Kevin at the track for some street tuning on the ride home. This was an extremely exciting point in the project, as I was able to experience full throttle for the first time, with the1 bar wastegate spring supplying a consistent 15-psi of boost. The results were absolutely breathtaking. The acceleration could only be upstaged at this point by the ungodly amount of braking power. Although, I suppose the insane braking will no longer be a topic of conversation when we are pushing 28-psi of boost out of the big GT72R air pump.
Jump ahead one week to a fine, Saturday morning… The car had run beautifully all week after arriving home from Waterfest. The only issue was that there wasn’t a back road in Harford County long enough to run out the top of 3rd gear - definitely a fun problem! Keep in mind, I’m supposed to be “breaking in” the new motor gently at this time, in anticipation of hours of tuning time on our DynoJet 248C. Well, unfortunately, we didn’t get that far. A sparkling new E46 M3 filled my windscreen as I navigated a big sweeper during my “gentle” drive to work. I laid out 3rd gear and rolled past him on my run to the top of 4th as we entered the highway. Now, to be honest, it wasn’t even close to a race. He’s probably still trying to figure out what low-flying jet violated his airspace. It’s really hard to find a challenge in this car. But now reality bites me right in the ass! As I start to lift at the top of fourth gear, with the M safely lost in the rearview, I hear a gut wrenching sound - the sound of a million little hammers banging away inside my power plant. Houston, we have a problem - Houston, we have meltdown. We still don’t have a clear part failure on which to hang our blame, it seems to be a compilation of many issues - the biggest being my unwillingness to stay out of that beckoning right pedal. We suffered a dangerous level of detonation that resulted in the destruction of four of our six pistons while thoroughly scarring the cylinder walls. The street tuning we had done on the way home from Waterfest, with an ambient temp of 65 degrees and a driving rain holding us to the middle of third gear to keep it between the lines, didn’t do us any favors in the 95-plus heat and humidity of a fourth gear pull. Other problems were found upon disassembly of the VR6. We had a deck height issue resulting in much higher compression than expected, and some sharp edges on valve reliefs that likely created hot spots resulting in temperature-related detonation. I ordered the pistons built to “drop in” the 92 VR6 block - no big deal there. Until, that is, you use a Mk4 Golf VR gasket in place of the much thicker Mk3 part. How we missed this rather important detail, I’m not exactly certain, however, I will add that when it comes to major projects, self-imposed deadlines can lead to all kinds of errors and oversights.
Now I’ll explain how we got this project back on track, and ultimately resulted in the more complete Rallye VRT you may have seen eating up Coastal Highway during H20 International weekend in Ocean City a few weekends ago. After the “incident” I immediately phoned Ross Racing Pistons for a new set of pistons, rings and wrist pins. These were .040 oversized and took our lump to true factory 2.9-liter specs. With new pistons in hand, the block traveled to the machine shop for a fresh cut. The rods were thoroughly inspected for damage and the crank was polished and cleaned for reassembly. Another call went out to our good friends at C2 Motorsports for a stacked stainless gasket to bring our deck height (compression) back in line. Along these same lines, the pistons were dropped down another half point of compression to be on the ultra safe side. Our measurements are now giving us an approximant compression ratio of just under 8.5 to 1. Which, by the way, is where we thought we were in the beginning. We also took this opportunity to have the compressor housing of the turbo polished, and many other underpinnings powder coated and detailed that couldn’t initially be done due to time constraints. The verdict: My itchy trigger foot, along with a good measure of impatience, cost me about three grand of the green stuff. That’s hard to swallow. But, the end result is a much more complete and capable car as compared to before. We have larger displacement, more built-in safety allowances, and a lot more “bling” for the kiddies.
The Rallye VRT is not unlike any other large-scale project car, in that it is an expensive learning experience that will be developed more each day I own it, and I will continue to share the development experience with VWvortex readers as we go along. It’s been a really fun project to have in our shop, and I can’t imagine a more fitting VW to put such a large effort into. The car is an absolute beast to drive, and is the most complete package I have ever experienced on the road (keep in mind we are only half way there with the boost!). Under full throttle, the top of second gear sees spinning rear tires and a lot of smiles. I can’t wait for some race gas and a little open road - God help those CV joints. We will shift from the technical preparation aspect into more of a tuning and race prep angle from this point. I believe the dyno tuning will be most enlightening for the many DIYs out there. This is one area that you need to fork out the dough and consult a professional, as my wallet can attest to! As always - stay tuned and stay safe! Links to previous Project Rallye stories: Part I Part II Part III Part IV
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