Hello Everybody I Got A Question I Don't Know To Much About It So Here..
I Going To Buy A Exhaust For My SS Sc I Just Wonder The Gmpp Performance It Come With A Cat Or Is Just From The Cat Down? The One That Is 17802111

 

it's a cat-back system.....it uses the factory cat. and bolts up behind it

 

Both GMPP systems are from the cat back, as sunburst said. To change anything with the cat, you'd need either a new downpipe or try and find a company who makes a header-back exhaust.

 

you guys rock! thanks!!!!

hey with my mod what hp estimation?
44lbs inj
2.80 pulley
nkr7 spark
gmpp exhaust
air box mod
hp tune
stage 2 belt

 

I would say you should be around 260 depending on how aggressive the tune is.