RJR99SS

I just got a nice daily driver 84 buick that i want to gut the cat on. Not exactly sure how to go about doing it, i did it on my 89 camaro, but that was just because the cat had clogged up. When i pulled it out i saw the catalyst inside was just all broken up into little chunk, i just shook it out and pried around inside with a screwdriver for a while and it was gutted.

I've heard of people cutting the cat open and just taking the material out in one piece, then welding it back up, but i dont have the tools to do that.

I didnt really want to replace it with a straight pipe cause i'd have to do some alot of fitting on it. With the cat i can just unclamp it, gut it and throw it back on. any ideas?

1986redbird

just on bolt the pipe from the end of it, use a long pipe or stick and jamb away, the catalyst is very brittle. a good whomp with a pipe will shatter it then just pour it out.

Mark A Shields

Gutting a cat isn't the best idea. From reading the exhaust board, it can interfere with the exhaust flow. Granted may not hurt, just letting you know.

DartByU

Yeah gutted cats hurt the flow more than help, and it also makes the exhaust sound hollow and tinny, I hate the way they sound, I can pick out a car with a cutted cat a mile away just by how it sounds. Put on a straight pipe or get a new hi-flow cat.

ChevyGuy87

when i did it to my camaro, i just unbolted it and shoved a big metal bar in through the inlet. it really is very brittle and comes right out

Dolph88sc350TPI

Like DartByU said, just put a straight pipe in if you don't live somewhere with emission inspection, if so then get a new hi-flow cat from catco, magnaflow, dynomax or something.

Also as Mark A Shields said, gutted cats will hurt flow more than help because exhaust gas won't be passing through the gutted cat very well due to turbulence(and sound like crap, IMO).

I know you said you don't want to do a lot of fitting but, there's a right way and a wrong to everything, and most of the time the right way is harder but worth your time.

If your monetarily challenged right now just wait until you can afford to do it right, and if you can't/won't do it yourself, pay someone else to do it.

RJR99SS

well how would you go about fabricating a straight pipe? i've never done any exhaust work besides pre-fitted stuff....