TJM Audi TT Convertible

Looks like the poor TR6 is going to stay parked for a while. After lavishing care and camshafts on his Triumph over the years, Peter Van Donselaar reluctantly admitted he hasn't driven the English roadster since taking delivery of his TT convertible. And now that the TT has dynoed at 375 hp and 398 lb-ft of torque, the next time the TR6 next sees a twisty mountain road will be purely for old-times sake.

Van Donselaar had "done an awful lot of work to the Triumph" over the years and didn't wait a moment before modifying the TT. After spending time searching the online TT forums, carefully sifting through the advice and opinions, he graced the TT with an H&R coilover suspension complemented by 25mm front and 19mm rear swaybars and a set of 18-in. O.Z. Crono Evolution wheels wrapped with 225/40-18 Bridgestone Potenza S0-3 tires. With the little convertible's handling to his liking, he went looking for power, "a lot of power."

After more searching and much filtering (or was that shoveling?) of tuners' claims, Van Donselaar settled on the proven Dahlback Racing 360-hp kit imported by TJM Motorsport and purchased through KMD Tuning.

Hans Dahlback has been messing with cars since childhood and cars equipped with his 360 kit have been storming around Europe since 2001. He reportedly blew up 25 engines (including a number literally sliced in half by errant connecting rods) trying to coax more power from the 1.8T after forming his performance company in 1997. The Dahlback Web site now lists kits with outputs up to 495 hp for Audi's version of the multi-valve four. Some of his extreme one-off race engines rev to almost 11,000 rpm.

Given this was the first 360 Kit installed Stateside, KMD Tuning's Danny Da Silva and Gino Giorgini brought the TT to TJM's Concord, N.H., facility for a final onceover and fine tuning.

At the heart of the kit are Dahlback's intake and exhaust manifolds, downpipe and KKK K26 turbo with custom internals (more than that no one would say despite repeated inquiries). Also included are new injectors, Bosch Racing F2CS plugs, oil and coolant lines, silicone hoses and assorted hardware. FYI, the turbo will support more than 400 hp while the exhaust manifold is good up to 700 hp.

With the stock internals stressed as far as anyone is comfortable with the 360-hp kit, Van Donselaar had the team install a set of Dahlback connecting rods for a little peace of mind. Good to 9000 rpm and 900 lb-ft of torque, the rods are the major internal change required for the next power stop-420-hp. "I'm more of a cylinder head, camshaft lobe-center and carburetor person," said Van Donselaar. "I have a lot of respect for these guys who are able to develop power through the ECU. A 110-cu-in. engine with 400 lb-ft of torque requires a lot of commitment. I needed to be comfortable with that because eventually I'm going to get used to putting my foot into it and I don't want any strange noises coming from under the hood!"

Van Donselaar did make one questionable decision. Despite TJM's advice, he decided to wait until the stock unit needed replacement before installing a stronger clutch. It didn't take long to start slipping, bringing the first tuning run on Rennen Performance's new F-1 4WD dyno to an early end! But it held long enough for TJM principal Tim McLean to breathe a sigh of relief as the chart showed 15 more horsepower than the promised 360. After a careful drive back to New Jersey, KMD solved the problem with a six-puck Sachs clutch.

"The next thing, desperately, is brakes," Van Donselaar said. "Even though I'm not usually traveling at a high rate of speed, I try to be safe. With the increased potential, the stock brakes-once phenomenal in my opinion-are now meager at best. KMD is going to install a set of Stoptechs. They'll get the job done!

"There are additional mods I'll be doing to the engine down the road. A set of the Dahlback Shrick cams, some work on the head for better flow characteristics (TJM's 420-hp kit also includes even larger injectors and a software upgrade) and possibly the Haldex controller," he said. The TT's computer controlled hydraulic center differential sends power to the front wheels first (though it will vary the split up to 100% to either axle) and some find the little roadster's handling more predictable with a permanent 50/50 split.

"Everything is going good, I'm happy with the car," said Van Donselaar. "It drives beautifully, very satisfying around town. Often with this kind of modification you get nothing at the bottom, but that's not the case here. True, it's no big block, you can't stab it and lift the front end, but keep your foot in it, wait a little and all hell breaks loose.

"I'm very happy with all the components that went into the car and I'm happy with the guy who installed them. I still don't know what nailing it in fifth gear is like-and I'm not likely to anytime soon. I nailed it in fourth and was moving at an alarming rate of speed. The real acceleration comes at 4000 to 4500 rpm, and in fifth you'd be going fast! I have a lot of respect for triple-digit speeds and value my license. The boost gauge goes 0-5-20-30 and the front end begins its side-to-side hunt for traction as the car hurtles down the road. It's like a marble shot out of a slingshot!" said Van Donselaar. "It's pretty intense."

What he said.