So my mechanic just put in my new 454 that I bought here off oso, I also picked up set of stainless marine exhaust manifolds. Mechanic issued a slight warning about taking it real easy coming off plane and also when going in reverse-he thinks the new manifolds sit lower (had an older set of some one offs previously) and is concerned the engine may take a big gulp of water....not so good I'm told. So is there an easy answer and put a taller riser in or should I swap them out for something else. Has anybody else encountered this before. Thanks

If the risers line up with the existing exhaust holes, then they don't sit any lower. You should have internal or external flappers on your exhaust tips also to help prevent water intrusion.

mount some exhaust flappers!!!

yep. Exhaust flappers are designed just for that purpose. Any competent marine mechanic should know this.

ok cool, flappers it is......now i no i can search this but you guys are way faster do they make flappers for turn down style tips

No. The turn downs should be connected to the actual exhaust tips and the exhaust tips should have internal flappers.

hey griff, im trying to picture the exhaust tips now....and i think the complete tip with turn down is a solid piece, or are the turn downs always an add on?