Greetings to everyone. I just purchased a 1990 mk3 turbo with 97000 miles on it. Car looks and runs great. I even took it to my local performance shop to make sure the engine, trans, etc... is in good operating condition. All checked out well. In regards to maintenance, I changed the oil, got new plugs and wires, k&n air-take downpipe, and test pipe to stock exhaust. The cars sounds better, however, I didn't notice a significant change in performance, maybe an 1 pound increase in boost. Is this normal??? Now looking for a good cat-back exhaust system. Not sure if I shoud purchase a muffler and take it to a local muffler shop to install, or should I just purchase a complete bolt on cat-back system. Please advise. Thanks
Cat-back exhaust
- Thread starter tbrian7
- Start date
Buy a nice downpipe and do the rest custom at a good exhaust shop. Welcome to the world of Supramania
If your going to invest in a good exhaust system, it would be a good idea to replace the stock turbo elbow, with a 3".
D7MSupra;1540120 said:
Thanks for the info. Actually, I already purschase my downpipe w/elbow from cx-racing, and my test pipe from the suprastore and installed both without any issues. Just a little surprised with the little difference in performance it actually made. I guess I really need to do the entire system to really see a difference! When I think about, I'm actually going from a 3" down pipe/test pipe to a 2.25 inch cat-back which is probably hendering the potential performance of modify the exhaust system. I hope to see better result when I get the 3 inch cat-back.
There's a thread on supraforums (probably on SM here somewhere too), which has a guide for upgrades. If you go straight piping all the way from the turbo to muffler, you can expect around a 40-50 HP gain. It's fucking awesome. You'll see the most gains when you get rid of the stock exhaust entirely.
The stock catback has a resonator and muffler that don't flow well at all. Get rid of that and your car will come to life!
The stock catback has a resonator and muffler that don't flow well at all. Get rid of that and your car will come to life!
want good power but dont mind being loud. Get rid of the stock cat-back and just drive open DP/Test pipe til you get an exhaust done. Thats if you wont mind it being extra loud LOL
Before you invest any more money in a catback do yourself a favor and replace the stock HG. Please don't ask me how I know. My first mod was a 3" raptor racing catback on the stock downpipe and elbow. Little change in performance or boost. My second mod was the suprasport turbo elbow with a used hks downpipe I got on the cheap. Lag times decreased and boost went up as well with the hks downpipe and elbow. Problem is your cx-downpipe like my hks downpipe has a restriction that cancels out advantage of a 3" pipe or exhaust. Finally I got a true 3" downpipe made by RT that replaced the hks downpipe....Wow! what a difference. Compared to the cheap restricted hks downpipe it was like night and day. Problem with cheap is that it cost more money in the end. All of this with the factory CAT installed by the way.
Did mention replace your stock HG before you spend any more money?
Did mention replace your stock HG before you spend any more money?