TransAmWS6

On average how much of an increase in power can be expected on LS1 powered cars when replacing the cat-back with an aftermarket one?

craz28

iTrader: (10)

10hp tops me thinks, not quiet sure though. what i would recommend is just get a cutout, cheaper and louder

ICEMAN 31

cut out will gain u like 13, then take the cats off or get high flowing cats and some good long tube headers and u will definetly notice a difference

TransAmWS6

Well I already have an SLP Loudmouth sitting in my living room just waiting to be put on, I was just curious what it was gonna do for my motor. Also, is a stock WS6 cat-back worth anything?

ULTIMATEORANGESS

iTrader: (4)

around 10 hp is normal for a stockish ls1. stock catbacks probably arent worth much since most go with better ones.

desertLS1

iTrader: (8)

I just put in the Loudmouth 1, not to long ago, I have an 02 SS, and i can honestly say that the feel increase in power is NOT noticable at all! The Loudmouth is also not much louder then the stocker, IMHO! My car is stock with just a lid, bellow, and CAI.

LS1Formulation

iTrader: (13)

My car was bone stock with a flowmaster muffler on it and I ran a 13.74@104. I added a lid and a Loudmouth and ran a 13.47@107. So between the two of them, I gained roughly 30HP.

SMKDFRD

I have the SLP Dual Dual low restriction exhaust package and I was wondering if i put a loudmouth I or II will it noticlbly louder that what i got?? I'd appriciate an answer

desertLS1

iTrader: (8)

Loudmouth II, not so much, Loudmouth I Yess. www.LS1sounds.com

greysteel_M6

iTrader: (5)

Depends on mods, maybe 10 on a stock car

Detoxx03

iTrader: (14)

I just put the LOUDMOUTH 2 on my car and I can definitly feel a difference in power with it and the whisper and smooth bellow I just put on. It sounds good also, take off is loud. cruising has a nice tone but getting on the accelerator makes it scream.

LT1_ownr

I had the SLP louthmouth on my LT1 and the only difference I felt was in throttle responce and a little on top end. But it sounded great IMO. Always enjoyed waking people up in the middle of night on my way home..