I've seen some resonated test pipes on Ebay. I know, quality is questionable, but they have advertised the bore as 60mm (2.36") - my question is is this the usual size bore that test pipes or high flow cats would be so they mate up correctly with the Y-pipe? I've searched for an answer but can't find any info on the bore size.

Thanks guys for any help and info.

 

60 mm is good. The end of the exhaust manifold is about 60 mm. It will match just fine.

 

https://my350z.com/forum/intake-exha...k-for-n-a.html
read post 15 it is all you need to know about exhaust diameter but as for quality that is up to your $$$

 

it depends on the Y pipe it's being mated to, assuming you're using the stock manifold