ok i want a nice exhaust system i want to pass emissions too and im have been looking around for a bigger cat would the 2.5 inch cat give any performance gains?

or should i go test pipe, how would i pass emissions do you test pipe guys put on your cats when you have too?

 

would u rly want to put it on and take it off every year? check with a shop and ask how they check.

 

Go with a high flow cat, some of them are pretty much a test pipe.

 

yeah, i don't think you'll pass emissions with a test pipe.