NWPC

I have a 1990 Warlock 24 Euro with a New 496HO, Bravo 1 drive with a 28p Bravo 4 blade prop. At 4800rpm I get 74mph with K-planes up. I get .21 slip using Merc calculator. To high? Where should I be? How do I get there? The boat planes very quickly, would going to a higher pitch be better?

Pat McPherson

If your drive ratio is 1:1.5 your slip is more like 10-12%.
I'd say you are hooked up real nice...

NWPC

would going to a higher pitched prop reduce the slip? & more speed?

Pat McPherson

The 496HO makes peek HP at 4900rpm so I'd say the pitch is just about right.
Labbing the prop for you particular hull design may give you more speed.
I would recommend you speak with Brett @ BBlades.

throttleup

The 496 Mag HO needs to run at 5000 RPM at WOT so you are a little shy now. You could lab finish your propeller for a 250 RPM increase and this should net you a little on top.

Julie

bbladesprops

Labbing the current propeller to match your boat would put you at the 5000 to 5100 rpm mark. We like to prop as close to 5100 as we can get with these engines.

Pat McPherson

Ray @ Raylar has stated in the TQ&A Forum that his dyno testing shows that a stock 496HO makes peek horse power at 4900rpm...
Now do you typically prop for peek horse power or slightly above?

throttleup

Actually Pat....most actually produce there peak HP at 5000-5100 RPM from the Dynos we have seen.

Julie

Raylar

Stock 496HO's tend to produce peak horsepower at 4950rpms to 5000rpms on the dyno. They do not have the horsepower fall off until about 5050 rpms. In the boat its best to prop to the 5050 to 5100 point to just stay off the rev-limiter and take maximum advantage out of prop speed. Our 525HP kits have peak horsepower at about 5100 rpms and the horsepower only falls off about 5 -8 hp between 5100 and 5300 rpms. After the 525 kit a 496 with headers and a rev-limit reprogrammed to 5400 rpms they like to be propped for a 5300 rpm max. Just thought I would add some facts.

Ray @ Raylar

throttleup

Thank you Ray...good info!

Julie