Got a HKS sport exhaust recently on my 01. My buddies claim it will sound and perform better if i bang out the filters from the cat's inside? ALSO might it throw a "check engine" if i do so? Any other recommendations perhaps? Thanks! Please Help.

 

i have mine done and mine is a cali spec car. the last o2 sensor is before the cat, if your's is before then you will be fine

 

sounding better is the ear of the listener. it will flow better with the cat gutted but no way will it pass emissions. you have an 01 which is cali spec so there is no o2 sensor behind the main cat so it will not trigger an ses light. if you dont have emissions to worry about then it might be worth very few up in upper rpms band if you had headers but otherwise i would just leave it as be until you replace the stock manifolds with headers.

 

Good deal thanks for the replies ....