I have been told by several people to get a test pipe on my exhaust. Is this something i should do or not? What will it do different if i do put one on? Will it add any horsepower?

Thanks,
Kevin

 

iam newbie but here is my attempt to input and hope not to get flamed.

test pipe = catless pipe

increase hp because it creates less back pressure.
it'll get louder and may sound better to some people's standard but it is illegal

 

Yes, testpipe = no catalytic converter.

On a 2002-2003 wrx a catless turboback exhaust will definitely add power, make it louder and make it illegal. Do you have any modifications done to the car? If not, I would recommend getting a catless uppipe first, then do the downpipe and catback.