31 Sonic SS twin 496mag ho's question
 

What props came stock with this boat and what speed would it run with those props?

Individual made mention of a leak back valve that clogged on one motor and having to replace the rubber between the engine and the hull exhaust? Where is a leak back valve on this engine and what rubber would you think it would be?

MY 31SS came with 26P. I run 72MPH GPS and I hit the rev limiter at this speed. I think the boat would gain a few MPH with 28P.

The only leak back valve that I know of was on my 28SS which had internal flapper valves to prevent a following sea from going into the exhaust.

Why don't you go to St Augustine and take it out for sea trials?

31ss
 

Thanks My Turn but not the boat I am referring too. This other boat is privately owned in LA.

2001 with 26P and I run about the same GPS 72 loaded. I am not hitting the rev limiter and thought about labbing to get a few more R's out of the motor however the stock 26P is a great midrange/cruising prop so I left it alone.

I've got a 26' Prowler w/ 500 efi and run 73(gps), 5100rpm. with 26p Labbed bravo 1.