Hey I have a 1998 oldsmobile lss non supercharged and was wondering if I can change the catalytic converter myself and what I need to do it any info would be appreciated thank you

ZZ performance has a magnaflow free flow cat that you can use. I use it on my 97 and have no problems with SES codes. You can change it yourself, but will need to figure out how you wish to attach it. With clamps, or welded in place.

Thanks but what clamps would I use and where would I cur the old one at u know the front connection is a flange

You can unbolt the flange and then cut after the cat. then you can cut the flange side off on the work bench, then clamp that to the new cat and get everything set on the bench. then all you need to do is line up one end of the pipe, clamp it down and attach the flange. You can use exhaust clamps, get them at any auto parts store.

Thank you dan I have found a catalytic converter with a flange already on it so when I cut behind the cat would I put the pipe coming off the cat into the resonator pipe and clamp it over the cat pipe or vice versa and how tight should the clamp be should it crush around the pipe or just tight enough to hold it

Hmm, how can I explain it. As the gases move threw the pipe they should never run in to a edge of a pipe. So, the pipe at the resonator should be bigger then the pipe on the cat. Tighten the clamp so it'* just crushing the pipe a bit. Then start the engine and check for leaks. If you have a leak, tighten again.

One more thing how can I tell if I have a leak the exhaust is one thing I nothing about on a car

You will hear a odd sound, like a pht or a tick. You can then carefully put your hand around the seams and you would feel air moving if there'* a leak

I'd search around as ZZP isn't always the best price. You'll also want to be wary and look under the car at the cat/flange. Most of the 96-99'* had the flange welded pretty much to the cat w/o any piping to work with. Clamping a flange to a cat won't work very well w/o enough piping.

My advice is cut out the old cat, and have the new on welded in. I took mine to the muffler shop and they only charged me $50 to do the work and kept the old cat. They sell them off for scrap.