Upgrading to 3" exhaust need help

[hubz91talontsi]

Ok..so Going to go from turbo back..Is a 3" Downpipe a direct bolt on to the stock o2 houseing? Ill be running 3" back with a 4.5" tip.. I have a stock 95 tsi. Can i run a 3" all the way down. Or would have see more horsepower out of the 2.5? I will be running a test pipe. Thanks i hope didn't confuse anyone.

 

[jemsoccer]

I had a 3" turbo back on my GST. It sounded great and allowed everything to flow real nice. I just bought a GSX and plan on getting a 3" back for that as well. Yes, the 3" downpipe should fit the o2 housing.

 

[hypnoticpimp]

I have the Apexi N1 downpipe with their N1 catback exhaust. At the o2 housing, the downpipe is 2.5 but quickly expands to 3 inches all the way back.

 

[ArcaineGST]

I also have the Apexi N1 setup. The downpipe and cat-back bolt directly together so no need for a test pipe. Also, Apexi already welded in an o2 bung for the rear o2 sensor. I've had it for two years so far and loving it. Hope this helps.

 

[marshall13]

I have a custom downpipe that was made by Abel Racing in Midwest City, OK. It's 3" all the way. You can have one made for pretty cheap and it flows great. Check out their website.

 

[hubz91talontsi]

Ok so the stock 2.5" o2 houseing will fit a 3" downpipe? I was just going to get a 3" downpipe..then a testpipe and go to the local muffler shop to finish the back. My brother took his stealth there. They did a very nice job. 4.5" SS muffler

 

[hypnoticpimp]

Since your mostly stock right now, there wont be a diffrence between a 2.5 and 3 inch. A 2.5 becomes a restriction when reaching close to 400 hp. If your plans are to go around 400 hp then a 3 inch will be necessary.

 

[hubz91talontsi]

Yes, i have 152k miles on right now plan on rebuilding into a 2.3 stroker over the summer. But will i see bigger gains from the 3" compared to the 2.5"?

 

[hypnoticpimp]

Since your building a 2.3, im assuming that you'll be running some high Hp. In high Hp apllications there is deffinatly a diffrence between a 2.5 and 3 inch. A 3 inch will be superior.

 

[hubz91talontsi]

Is this ideal for right now? I still will be doing the 3" i just want to know if its going to give me what i want? LOUD AND POWER.

 

[91dsmgsx]

if you want your car to be loud and get a little bit more power go with the 3in all the way back. i have a megan racing 3in down pipe and straight back 3in exhaust.....its awesome go with it

 

[hubz91talontsi]

Ok thanks guys for all your help.