Up to this point, our 2009 VW Jetta TDI has received a set of 19x8" BBS CH wheels, 235/35-19 Continental CSC3 tires and KW V3 coilovers. The car sat right and handles well, but there were other issues to be addressed. For starters, the stock brakes are mushy. Press the pedal hard and it's like stepping in custard. While they probably work well enough, we definitely wanted to improve the pedal feel, so a set of EBC pads and rotors were enlisted.
We also wanted to start looking at power-adders. The Europeans have been tuning turbo-diesel since prehistoric times, so we thought it was time to get in on the act. A cat-back exhaust from Techtonics Tuning and a cold-air intake from Euro Sport Accessories would be our first modifications.
In the following article, we'll look at the fitting procedure and detail the dyno results. For complete step-by-step installation photos, though, please visit our website at www.eurotuner.com where we have more space to show every stage in the process.
The task of installing and testing again fell to our friends Raffi and Vik Kasanjian at Euro Sport Accessories in Anaheim, CA. They recently worked on our Project B6 (et 5/09) and offered to help with the TDI as well. It would give them the opportunity to prototype their intake for the car, so we were happy to help. In addition to manufacturing many of their own parts, Euro Sport has extensive expertise working on all kinds of VWs, with racing Mk1s and Mk2s littering their large workshop. Plenty of Ford Focus stay at the shop as well since they run Focus Sport.
To begin the day, Vik strapped the Jetta to the dyno to record a baseline power number. Unfortunately, Euro Sport's dyno isn't able to read the RPM signal from diesel engines. Therefore, we couldn't plot torque output. So we'd stick to the power readings and record them against wheel speed rather than RPM. While not ideal, it's still relevant for comparison testing to measure increases.
On the first runs, with ambient temperature at 69?F, the TDI recorded 130, 131 and 132whp. This was very consistent and surprisingly high for our 140hp engine. Accounting for transmission losses, our car actually delivers about 150hp, which is good to know.
Techtonics Exhaust
Having waited several months for Techtonics to complete its new 2.5" stainless steel cat-back system, we would be the first to test it. Two versions are available with either single ($605) or twin ($680) tailpipes and both use a single Borla muffler.
Before starting, we noticed the car uses two catalytic converters and a complicated valve that resembles a throttle body. This is sophisticated emissions equipment that allows the TDI to comply with US regulations and we wouldn't be tampering with it. However, it was inevitable that this was where most of the exhaust's restrictions would lie.
You can follow the fitting steps in the captions. Once installed, we returned to the dyno to measure the power increase. The temperature had risen to 80?F and our three runs produced 131, 132 and 132whp. Even allowing for temp corrections, we weren't looking at an increase anywhere in the rev range.
On a positive note, the exhaust wasn't noisy, so it didn't amplify the tick-tick-tick of the diesel engine. Yet we did now have attractive chromed tailpipes protruding from the bumper, so we had a cosmetic improvement at least. And we're hoping that with more mods down the line, the exhaust will come good. Although we suspect that the emissions equipment is the real problem.
 1. The emissions equipment...  1. The emissions equipment in the exhaust is unlike anything we've encountered before |  2. Stock exhaust is fitted...  2. Stock exhaust is fitted in one piece, so needs to be cut over the axle to get it out |  3. Then unhook the rear hanger...  3. Then unhook the rear hanger and Vik demonstrates the rear muffler being removed |
 4. Loosen the clamp that secures...  4. Loosen the clamp that secures the system to the downpipe, unhook the remaining hangers, and the center muffler section will come away |  5. Photo shows stock exhaust...  5. Photo shows stock exhaust alongside TT. The latter is much longer and the rear straight pipe must be cut down to fit |  6. Vik hung the TT center...  6. Vik hung the TT center muffler so he could measure the gap to the downpipe. The rear hangers are fitted to the TT clamp that's supplied |
 7. Our car needed a 4" section...  7. Our car needed a 4" section cut and inserted into the center muffler. This is then clamped to the downpipe |  8. You can now hang the rear...  8. You can now hang the rear section and secure it to the muffler with the clamp provided. Washers are provided to align the rubber hangers and prevent the exhaust sliding off. Don't tighten the clamps until you have the system aligned under the car |  9. Once aligned, the chromed...  9. Once aligned, the chromed tailpipes should sit perfectly in the rear valance, as ours do |
 10. Dyno curve after the exhaust...  10. Dyno curve after the exhaust fitting shows almost no difference between stock or TT exhaust | | |
Check out this projects extended version when you click here.