Anyone know what gasket i need for the outlet of the cat to the rest of the exhaust? I cant find it anywhere, well not one that fits. I'm running a stock cat and a GReddy EVO2 catback but the difference in sizes is causing the problem so im using a 3" o ring doohickey that just wore out and created an annoying whistle. I might just take off the exhaust and make a template and have someone match it.

 

wehn i got my catback the muffler shop i went to had a doughnut that fit perfectly, check around at muffler shops and auto parts stores