2007GTCS

I'm looking into catbacks and was wondering what experience anyone had with proven rwhp gains with the various options available. I don't want to blow $ on just sound.

ANBAUTO

Ive got the magnaflow 3inch magnapack catback system and thier high flow catted x-pipe and i did see an increase with this setup.

CrazyAl

A different X-pipe or H-pipe can give you HP.

However, on this car, catbacks are not worth any HP. The only difference between the catback and mufflers only (AKA axle-back) is that the catback comes with overaxle pipes too. The issue is that the OEM overaxle pipes are already great. You don't gain anything by using a catback as opposed on an axleback. And for that matter, changing either one (Catback or axlebck) won't appreciably change your HP.

If you want HP you need headers and/or highflow cats (or no cats, AKA "offroad pipe).

You change your mufflers/axleback if you want to change the sound.

my77stang

so what kinda gains are you supposed to get with axle backs? flowmasters for instance? this post was a buzzkill for me

CrazyAl

None. Axle-backs do not provide any appreciable HP on these cars.

As I posted above, axle-back changes are for SOUND. If you want HP gains from your exhaust then you need to do headers and/or midpipes (high-flow cats or offroad type)