My mods are in sig. Would it be better to get afull 3 in. exhaust from header back or would it be too big. Im gonna buy a header,dp, and catback soon. Im also installing the 3" throttle body. I wanna get the most power from it.

 

Uh, depends on your ultimate power goals! 3" is good for your mods!

I have 2.5 and I think I have found it's limits now!

 

idk, i think u'd be able to get away with a 3".

 

Alright thanks ill definately be modding more so i guess it will be a good idea.

 

Yeah, if you deff. plan on going beyond what you have 3" will be what you need!

I'm a high 260hp car with a 2.85" and I have maxxed out the 2.5" pipping!

 

The differences seen between the two i think have just been a small maybe 1-3 horsepower increase on the top rpm end for 3" and a 1-3 ft-lbs of torque loss below 3000 rpm or something with a modded cobalt (someone did the comparison on a dyno somewhere, the difference is pretty negligible for most setups. Biggest difference you'll have is the sound though, if you don't like ungodly loud exhausts a 3" may not be for you then.

 

I just got a CA header from someone off of the site. From reading past threads i figured out im gonna go with a custom 2 1/2" catback. Im most likely gonna get a muffler to replace the resonator and get dual 4" tips kinda like an srt-4 exhaust. Now my question is i see some other people on the site use a 3" dp with a 2 1/2" catback. Which one would be better and can i install a dp to the factory catback? Thanks

 

3" for an S2+ LSJ

 

anyone else?????????

everyone has a different opinion some say a 3" is fine others say a waste cause its not turboed

 

If you're not going to take our suggestions why did you even post this thread? Go with a 3" or you'll regret it.

 

I think 2.5" is fine.3" is over kill unless ur going for some crazy hp numbers.2.5" exaust is more than capable of supporting atleast 350 hp.I dont see how you can say ur maxed out with ur 2.5" exhaust.But,to each there own.