are there supposed to be gaskets for the cat?

(85 z28)

 

No....

 

didnt think so but i just wanted to be sure.

 

any one know what bolt size is needed for the catalytic converter? mine are rusted pretty bad i think they are a 17mm head, but what about length? i tried to pull one but they need to soak a little more...

 

If you're talking about the back of the cat, then yes there is a "gasket." But it's a round donut, about 1/4" thick, that sandwiches between the flares of the cat and exhaust pipe. It could be made of either a composite or solid steel. Can't remember the size of the bolt though. Best way is to get the old ones off and take one to the store. Heat the old ones up real well with a torch too.

 

im putting in a high flow cat, is that "gasket" re-useable? nothing pops up in any searches for a new gasket so im leaning towards yes...

 

You can reuse it if it doesn't get torn up when you take the system apart. Otherwise auto stores have them for a few bucks.
BTW, is your new cat a "direct fit" or a "universal replacement?" Direct fit will have the same flange as stock to mate up with your exhaust system. A universal one will have a straight outlet pipe and you'll have to cut & splice your exhaust up to it.

 

it's a magnaflow direct fit. it bolts up on both sides. sweet thatswhat i wanted to hear, no worries then.