Slight correction:

A good rule of thumb @ .050 staying under six - 8 degrees of overlap should keep you fairly safe correct with good wet exhaust...this is what Crane has preached.

Sorry Had It reversed thank you

I ran the livin dog chit out of those 561's MT mentioned. Never any issues. Those cams in a 454 run well especially with some aftermarket good flowing heads. I ran with Jim v assisted dart 265 oval port heads, torker two dual plane intakes and 9022s. Good running combo at a conservative 480 hp. I'd run again in a heartbeat but not without zinc additive.

Yes and no. As stated earlier, the crane 134561 236/246 114, ran just fine in my buddys 454's , with stock cast iron center rise exhaust. For many years. That cam had 13* of overlap at .050 .

I ran the 741 roller, that had 16* of overlap at .050, with stainless marine manifolds, that had short bravo risers, that coupled to the tips just like yours does, with no reversion issues.

Mercurys 525 EFI engines cam, had 12* of overlap at .050. They ran wet exhaust with silent choice diverters.

All that overlap talk, but heres another option. Find a friend or someone local who can Tig Stainless. Get your hands on some stainless pipe, and have them extend your current risers, to go all the way thru the transom, and eliminate the screw on tips/rubber coupling. If you find its too loud, you can install some Gibson turn downs, some clamp on bullet mufflers, some switcheable air activated mufflers, or some drew marine shotgun tips, or , many other options, and run the cam the engine will like.

Yes, many have used the Stainless Marine and the 741 . Good point.

Joe you ran 741 in 454 NA? Or what that in your SC builds.

Thanks everyone for all your input and help!