Crusader 454 rpm at cruising speed

" I am looking to purchase a 3

" I am looking to purchase a 36 Silverton with twin 454 crusaders, 320 hp. Does anyone know what rpm's for cruising speed. Sea trial was about 20 mph at 3800 rpm. Want to go faster but not use alot more fuel. "

" Your ideal speed is almost e

" Your ideal speed is almost entirely dependent on your hull, not the engines.

I own a 36 Trojan sportfish with twin 454 crusaders (350 hp), and optimal planing speed is 3100-3400 RPM.

You say you want to go faster than 20mph? Not without burning MUCH more fuel. Anything over 4000 RPM is way out of the efficient range. Plus its hard on the engines if you have the idea of crusing @ more than 4000 for long periods of time. "

I have a 1998 Regal Commodore

I have a 1998 Regal Commodore 402 w/ twin 310 hp 454's. When we first got the boat we clocked it at about 32 mph top end (with a ski boat). Late the 1st summer we bent both prop shafts which we had fixed. The following summer we noticed that the boat seemed slower at WOT. I installed a new GPS and at WOT the GPS says the boat was only going about 20-21 knots. I contacted Regal and they informed me that the props on the boat are supposed to be 22x26. We recently had the boat out of the water and discovered that the props are actually 22x24. It seems to me that if it had the correct props then the RPMS would be less and the boat would be slower at WOT. It runs at about 3600 rpms right now and I seem to remember it ran at about 3800-4000 when we 1st got it. Is this a engine problem or a prop problem??? The engines seem to run fine but perhaps there are fuel/ignition issues that are causing the engines to develop less power??? It seems odd that both engines would be performing below par but I guess stranger things have happened. Any ideas??

Sorry about that.. I thought

Sorry about that.. I thought I was in the "Gas inboard engine" section... I moved it.