hey i just bought a 91 rs LO3.

it has what looks to be like the cat was removed along with everything after, it has a glass back in place of the cat and just ends there.that mother****er is loud my ears ring after i drive it.

a lot of people have told me the car is running a lot slower because of the exaust and that it run ALOT better and faster if i got a hiflow cat and exaust. so my question is is that true?

it is a stockLO3 as far as i know with just an open elemnt air filter pretty much.

 

You would notice little, if any performance difference with a full catback and cat on there. You might be down on torque a bit, but it won't seriously effect the way the engine runs.

Don't be fooled...the LO3 is by no means made to be a performance engine.

 

haha yes yes i know but a guy told me that having no exaust pretty much cuts the backpressure of the motor so much that what little power it does have is gone

 

i'll agree with that- when i cut my old muffler off right behind the cat, the car did seem to lag a little. when i got my new exhaust system, there was definitely a small, but noticeable difference.