how does the header perform,and how much hp gain with a gmmp performance exhaust,header combo.

 

The vibrant header is a complete replacement of the stock manifold, downpipe, and cat.

As it is a long tube header, with a downpipe and high flow cat. This is why it is a bit more than other places, but it is the most complete kit out there.

IMO i would get the Vibrant exhaust or the Corsa brand. GMPP is the same diameter as stock and just has a better sounding muffler on it IMO...