I've been saving up and am now thinking about gaining some power under the hood. So that being said, what exhaust has the best HP gain for the 8?

 

catless midpipe and catback you MIGHT AT MAX see 10HP dependingon what system you get you're looking (for midpipe and cat) prob at LEAST 500 bucks that's going with the cheapest exhaust and cheapest midpipe..'

BTW search is your friend you better learn to use it or permanently live in your flame suit!!...

 

midpipe alone gives you 10. But both of them together would probably around 12-13whp. I recommend the BHR midpipe and a Racing beat Rev8 Catback. For me they are the quietest and one of the best systems to get.

 

get the turboxs headearback exhaust (loud) but i felt more power and more torque, its a 3 inch exhaust

 

Wrong. Racing Beat basically ran an open exhaust and got a total of 10 hp. A midpipe alone won't give you 10 hp. Import Tuner did a midpipe change & got about 6 whp, but strangely, no tq. gain.

The answer to the OP's question is none of them will give you more than 2-3 hp, so you are better off getting one that sounds the best &/or looks the best to you, or is the cheapest for you.

Unless you are getting turboed the hp gains from even a full exhaust won't be super great.

 

3" is probably too much for most NA cars around here. Bigger doesn't always equal better! a pipe that is too large will slow the exhaust gasses down

 

global warming dude..don't get a catless pipe