has any one used stainless marine gen 3 exhaust on a 632ci na motor or is it to restrictive

If that is the biggest style they make, which I believe it is and has a 4, 5 or 6 inch tail pipe you should be just fine.

I think the 5 inch tailpipe and u are all set ,,,would not go with 4 inch !

Scott, what's up dude ? you board again stuck @ the comp. screen ! j and yes bigger is better, seen many a set of 588's NA run thru-4inch true with no issues @ 5600

Bored ,,,just like you. On a 600 + ci i would not go with a 4 inch though.
I seen it done but i would be scared of to much back press.
You put more in u need to get more out.