Best performance combination

" I have a 79 Mastercraft 19ft

" I have a 79 Mastercraft 19ft ski boat.(shallow V hull)
It has a 351W 4v engine. I am only getting 3400 RPM at WOT. with a speed of <40 MPH. The prop is three blade OJ, 13X13, brass. I have inspected the carburator linkage to to be sure that it is at WOT. The owners manual for this engine says that engine RPM at WOT shoud be around 4500. What cam /prop combination would yeild the best overall performance with this hull? "

Hi Greg!
I would check out i

Hi Greg!
I would check out if the secondaries are opening since these are vacuumoperated. You can not do this without actually driving it since they demand a load to work. Get someone to check them when you go from normal speed up to maximum. If the fail to open under these circumstances I would guess that the diaphragm could be broken.
Peter

"I'm with Peter on this.

"I'm with Peter on this. Your 351's low rpm's are most likely the result of a mechanical problem, not the need for a rebuild. On the fuel side, check for proper fuel pressure and make sure all filters are clean. On the ignition side, I'd check the ignition advance weights in the distributor and verify the timing with a strobe light. Your engine should have roughly 35 degrees total timing above 2500 rpm.

13x13 props are the standard size for most tournament style ski boats and should result in 4400-4600 rpm for most small block engines. Check your prop and shaft for any fouling, too.

"