Originally Posted by future370zzz

Mark, won't the stock cats burn up and need to be replaced after a certain period of time? Also, isn't there potential for the stock cat debris/burnt material to get back into the engine?

How much power is lost from going to test pipes? I'm currently using test pipes. My power/tq is listed in my sig.

Originally Posted by Team_STILLEN

I would advise going back to stock cats. We have seen significant power drops when using HFC's and Test Pipes with our supercharger. Also, if you are planning on going with the 9 lb pulley you will need at least 600cc injectors and I would recommend UpRev GT MAF's to make tuning easier.

Are you on 93 Octane?