Custom exhaust

Im planning on taking my car to a local exhaust shop and having them cut and bend 2.5 inch pipe for my 99 gs. I have a few questions:1) does anyone know where I can get a modulator to remove the o2 sensor in the Cat so I can cut it out? 2) Will 2.5 be big enough for whenever I get a turbo? 3) if I cant get a moudlator should I get an Arospeed high flow cat? 4) What would be a good (preferably somewhat cheap) muffler and tip that would sound alright and not like a pissed weedeater?

Thanxs in advance

JrS

Hey,

2.5" Exhaust will be fine. As for a muffler just use a Borla or Thermal research, those two I know have a more mellow tone a lot of the ebay knock off mufflers sound terrible. Just make sure you get the right diameter in an out. For a tip, just pick one you like and have them weld it on.

Lastly, go to www.vfaq.com and look at the thread about removing the second O2 sensor. Its a little soldering but really simple, I did it in under and hour. A point of advice, if you opt for a high flow cat, you can keep the rear O2 sensor with no problems. However, I would suggest removing to O2 sensor and running no cat if you can, more power.

Hope that helps.

2.5" is good for most turbos, but if you think you may go to a big one eventually, get the 3" now. I wish I did ;) But its good for 11s. For the 2nd sensor, mine kept throwing a code every 2 days for a couple months. Eventually it jsut stopped. Some poeple never get it, some people cant gte rid of it. Only one way to find out ;) If you leave it plugged in, wrapped in foil, and ziptied up underneath the car the ECU should get over it eventualy.

Hey thanxs fo rthe info. Aves911: Im having a little trouble understanding the 02 mod. Do I have to buy any thing or just rewire the things that are already in there? Also what do you think of a Flowmaster series40 muffler? i can get them for about 50 bucks. Last thing, should i go with offset offset, or center offset ?

Thanxs,
JrS

The flow master mufflers dont flow well enough for a turbo car from what I've seen. In fact, nothing comes close to the straight through mufflers based on flow testing done by a local guy. Namely the Dynomax Unltraflow (either Welded, or Stainless), and the Magnaflow. The typical setup is the 6" round by 12" long, 3" center in/out, or 2.5"