There Was A Time When Frank Hart's Oil-Burning Corrado TDI Coupe Would've Been Ridiculous, But Now It Doesn't Sound So Bad
Within any group of brand-loyal diehards, there are always smaller sects who stick to a certain model or engine within that range. Audi has its five-cylinder loyalists and BMW has E30 fanatics, while VW has diesel engine and Corrado enthusiasts. And it follows that somebody who's infatuated with both and has the mechanical ability to combine his passions means you've got a sure-fire winner.
Frank Hart, the man responsible for desecrating the VW altar
Frank Hart is just such a person to tackle this uniquely juxtaposed engine/chassis swap. He's a Corrado guy through and through, who's owned no fewer than 15 of these coupes over the years. However, his conversion to the TDI religion occurred in 2001, when a friend's chipped Mk4 TDI kept pace with a worked Corrado G60 and still returned 50mpg.
However, the ultimate Corrado has always been the VR6 model, so when presented with a great deal on a '92 SLC VR6, he jumped at the chance to own it. Yet things weren't quite as they seemed.
"I bought it in the middle of winter and it had what I thought was condensation coming out of the tailpipe. Little did I know it was actually oil," Frank told us.
Efforts to correct the problem went from bad to worse, with each more complicated repair yielding zero results. A warped block was ultimately diagnosed as the culprit.
"In the end, I was tired of working on it," Frank reported. "I could have easily swapped in another block, but I sold off the powertrain parts and left the car to sit while I concentrated on a 20v G60 conversion with stand-alone engine management."
In the meantime, a TDI swap had been playing on his mind, but the scarcity of low-mileage motors and the high price of anything with a TDI badge meant it was a costly dream, at best. However, fate would intervene when Frank planned a big step for his primary project. "On the day I planned to take all my money and put it towards SDS for my 20v G60 project, I found a great deal on a TDI," he said.
The '99.5 Mk4 Jetta TDI was damaged on all four corners and he had to tow it home. After the VR6 fiasco, the Mk4 powertrain was thoroughly tested.
Some might consider it overkill to repair a car you don't plan to use in order to check the motor, but as a bean counter for the city of Norfolk, NC, Frank always plans ahead.
Looking like it belongs, the 1.9 TDI took ingenuity and perseverance to get it there
Once everything checked out, the complex task of installing the TDI engine into the Mk2-based Corrado began. As you might expect, wiring proved to be the biggest obstacle, especially since Frank didn't want to cut any additional holes.
"Whenever I got fed up working on the wiring, I'd work on the mechanicals," Frank continued. "Bolting the motor into the car was probably the easier part of the process, but whenever I thought I had it figured out, there would always be an obstacle. I built the pedal cluster twice because on my first attempt, I built it with the Mk4 brake booster, but it turned out to be too large and interfered with the Corrado clutch master cylinder. There were so many different issues like that."
Some of those "little" problems included matching a variety of brake lines to install ABS in the SLC. "I had a tough time figuring out the lines going from the G60 master cylinder to the Mk4 ABS module. You have a 10x100 fixing on one end, and 12x100 on the other, so you have to make a hybrid line. Fortunately, I decided to go rummaging through a junkyard and I eventually found a Passat I was able to pull lines off," Frank said.
"The ABS works great. The Corrado's older ABS, when it would engage, would feel like you had square tires. But this new ABS just gives a light pulsation and actually keeps the car straight," he enthused.