What you will get is lots of noise that will confuse your senses and make you THINK you have more power. But if there IS more HP it will be at high rpm where the lil Jeep engine fears to tread.
In order to get more exhaust OUT one must first allow more gas INTO the engine. So unless one does an expensive HEAD JOB and intake system and then intends to run at much higher rpm, the fancy exhaust will be of no use to the Jeep. Dual exhausts actually HURT low rpms, as the scavenge effect of the pipes doesn't start working until a certain velocity is achieved.
Big Jim <img src="/forums/images/graemlins/pfft.gif" alt="" />