Originally posted by hype8912
You wouldn't get a thing. You would still have the same amount of backpressure in the pipe.
I have Tanabe Race Medallion muffler, custom 2 1/2 inch pipe to cat. High flow straight through cat. ( Basically a cherry bomb muffler) Thats where I stopped in hopes of dropping an h22 in soon.
To just mod your stock exhaust. You can cut off the resonator and weld in a straight pipe.
dude you still get some HP increase.... taking out the stock cat and replacing it with a highflow cat will create better breathing in the car.... however i dont recomend getting a high flow cat with the stock exhaust..... buddy of mine did that, and it sounds like sh**...... just get a catback.... you don't really need a highflow cat