Any recommendations for nuts/bolts suitable for connecting an aftermarket y-pipe to an aftermarket (both Magnaflow in my case)?

The original setup had studs in the y-pipe, which is not present in the new setup.

So, size and grade is what I am looking for help with.

Thanks.

- Chris

 

I chose M10 bolts (~2.5 inches in length) and nuts with a flat and split washer. They appear to fit well but it almost looks like M12 might work as well and be a bit more snug in terms of the inner diameter of the muffler to y-pipe flange holes.

Plan is to get the new exhaust system in within the next 2-3 weeks (weather/time permitting), so I will have a final report on the bolt size here once I'm convinced what actually worked.