what would be the downside with having a 3" catback and 2.5" performance cat zzp dp, WITHOUT the header? Thats the setup I got now and it backfires (you can hear it.) and it seems like I lost power, like ALOT.

could it be an exhaust leak? or does it need another good tune? either way im still getting the header.

 

A 3" catback with a 3" pulley is way too big, you should stay at 2.5" at the largest. Going from a 2.5" DP to a 3" catback doesn't make any sense either.

 

thanks alot! you have been very helpful. I tore off my 3" catback and put a 2.5" on right quick. because I have a hole bunch of exhaust components just hanging around in my garage.

 

No problem.

 

My setup is on stage 2, with a 2.5" high flow cat downpipe, and a 2.5 exhaust.

Downpipe isnt on yet.. hope it sounds good, and adds some ok power.

 

yea right

 

is this sarcasm or in agreement with him? I know the cat back might be a little big, but shouldn't cause the problem im inquiring about.

 

Unless you are going at least 2.8" pulley or smaller or TVS having a 3" exhaust is going to hurt your low and mid range power. Sure, you might gain a little HP up top but you lose HP and TQ in the low and mid ranges which really isn't helping at all.

 

I mean yes I understand, but I figured I was going to max out on mods sooner or later so might as well get the 3" exhaust . nah mean? btw im getting a 2.7" pulley.