I am wondering if i can put on my punched out cat and send it to an exhaust shop to get the rest put on? Will they say anything about the cat being punched out... i've heard both sides of the story so idk. WHat do you guys think?

 

Well last year I couldn't find a single shop that would put on an exhaust without having the cats on. All of the shops I called were either national chains or bigger locally owned shops. Well I finally asked around enough and found a small auto repair shop who did exhaust as well. They did a pretty decent job considering the amount I paid. My X pipe and mufflers hang a little low but I can live with it.

 

Your location is an emissions state. You might have a hard time getting an exhaust shop to work on your car "on the books".

 

what about backpressure? i bought a cheap high flow cat its only about a foot long. Will it affect my hp much or no? if i look i can see through it a little....

 

What about backpressure? Read the sticky on this subject.

A high flow cat may get you another couple of hp. You have to re-do the entire exhaust to really see a difference.

 

Do you mean opposed to a standard cat?

 

The answer is it depends on the shop. I don't think they can really be pinned for working on a car with a gutted cat... as in they can probably do a cat back for you with no legal reprocussions. The inspeciton is only visual, so a gutted cat will pass inspection (assuming you're not in the NYC area where they would put your car on the sniffer).

That's the only thing that can make sense... because a straight pipe will be most efficient, follwed by high flow cats then OEM cats.

IMO High flow cats are the way to go, they only really steal maybe 1-2 Hp compared to a straight pipe. The backpressure caused by a cat is minimal and probably won't effect your powerband.