A VERY nice 1993 Trans Am I will most likely be buying within a week (I'm so happy to finally get a T/A!! ) has had the Catylytic converter hollowed out. Basicly, the owner heard a rattling coming from under the car, and realized it was the cat. He brought it to his buddy's shop and he told him it would be about $300 to replace the cat.. he didn't want to remove it, because even though there are no emmisions tests in my state, it is still illegal. So, instead they completley hollowed out the cat... all the chalk or whatever is inside was knocked out, so its just a big empty drum. Then it was put back on.. no more rattle


My question is, do you think the car gained any horsepower from this? Also, the car is QUITE loud and throaty. VERY nice sounding. Would hollowing out the cat really make the car much louder, or does it have a custom exhaust that he might just not know about (from an owner before him, maybe)

Thanks!

 

It will change the tone and make your car louder.

Gained any HP? Yes. A lot? Nope.

 

yes it will change the tone and make it louder. yes it is illegal to hollow out a cat, just like not having one.
yes you gain HP but your trading it off in a loss of torque.

 

Thanks!

I love the tone like that. I wonder how it will change if I do custom exhaust/headers later on?

 

WAAAYYYYY louder......what you may even call, too loud

 

My car was quite a bit louder when I got rid of the cat. You can expect a small gain in HP and no loss of tq.

Aaron