Okay, I've tried the Techtonics Tuning 2.5" stainless steel exhaust with 2
resonators, a venturi, and a resonated tip, and it *still* resonated too
loudly in the cabin to be an acceptable solution for my daily driver GTI
I have since purchased and installed the Jetex 2.5" stainless steel cat back
exhaust ($583 including shipping from New Dimensions).
So far, I'm very pleased with the Jetex exhaust. It's *much* quieter than
the TT, yet is still louder than stock to let you know it's there. Think of
the TT at half volume or less. It has a nice, sporty tone when you get on
it, yet maintains a civil volume level inside the car. I'll try to get some
in-car video of the Jetex soon-ish. In the meantime, video of stock and TT
exhausts can be found at <http://members.home.net/dubvidz>.
When the system is cold, is as quiet as the stock exhaust. Once it warms
up, the volume increases, as the TT did--but is much quieter than the TT.
Likewise, conditions that caused the TT to get louder will also cause the
Jetex to get louder (i.e. going up a small hill in 5th, romping on the gas
pedal, etc). However, the louder sound is NOT accompanied by the in-cabin
resonance I got with the TT. The louder tone is not bothersome, and is
easily drowned out by the stereo at low to moderate volume. Holding a
conversation while underway is not a problem. Traveling at speed on the
highway/interstate is just as comfortable as the stock system, yet has a
nice growl when you get on the gas.
Performance gains seem to be on par with the 2.5" TT exhaust I had
(butt-dyno measurements only). My DSR 256 cams seem to breathe nice and
freely now, just as they did with the TT. The stock exhaust did seem to be
a bit restrictive, and both the TT and Jetex exhausts feel like they've
I had my trusty independent VW mechanic do the install. He didn't complain
of any difficulties, so I guess the installation went as smoothly as the TT
install. Fit and finish on the Jetex system appear to be quite good. The
stainless steel on the mufflers and nice twin 80mm round tips is polished
and shiny. (I hope to get some pics up on the web site soon-ish, too...)
In conclusion, I'd say the TT exhaust offers the best value when considering
performance versus cost. However, if your car exhibits the dreaded TT
drone/resonance between 2k and 3k rpms (or if you fear it might) and don't
care for that, shelling out some more bux for the quieter Jetex exhaust is
what I'd recommend, since it appears to perform just as well as the TT at
half the volume or less.
'95 GTI VR6
'84 Scirocco Wolfsburg Edition