Could I weld the stock cats into the mac oryp and still have good flow.

I would open up the cats to 2.5" hole size so it would fit the oryp

I'm going to cut the collector out and go duals into sweet thunders and out the back.

Do you think it would sound good?

 

you cannot attach stock cats to any aftermarket Y pipe. Reason being one is on an angle with the exhaust manifold. Best to trash them completely or get higher-flow ones, like Magnaflow.

 

If I cut the pipes completely off of the cats it would work.

 

I've looked at my cats and it can be done, I've read of guys doing this as well sicne they flow better than the Mac cats. Just cut further enough in to make the hole big enough. I plan on this route just to save money, when they blow I will put the ultra high flowing soundcat cats in there.

 

Your ORYP is 2.5", not 3"? Did you get this to work with stock cats?