lets say I have 500 crankshaft hp. will install bravo-1
what would be the prop. hp?

I think that you'll be surprised at how much you loose on most outdrives. You're turning the power 90 degrees, twice.

I would guess, and I'm only guessing 15-20%

I've always assumed around 50hp.

Correct me if I am wrong but:

502mpi = 450crank = 415bravo
Hp500 = 500crank = 470bravo
575SCi = 575crank = 550bravo

I would think Mark that the figures that you are quoting are only advertised HP, and that jdncal is pretty close to being right at around 10 to 12 percent loss. Im sure that some of our members can rally tell the exact amount of hp loss.. Im just giving my two cents worth...
eliminator219

Eliminator219, you are correct, that is just what i read, which can also be deceiving at times.

Friend with twin HP500's(approx 50hours) got them prop shaft dynoed, and well, just a little disappointing what the sheets said and also how far off the two motors were. All i can say is if you want to know how much hp you have, pay the money and hook it up to the machine.

I have always heard 10%

Not trying to make a mountain out of a mole hill here, but I have heard 25-35 horsepower loss throught the Bravo One. I honestly don't think a percentage is accurate being that the outdrive doesn't know what the engine is making----the drive only takes what it needs. Just think if you had to run power through a tranny too----there's more horsepower that you lose. It's only my .02

The more HP load on any drive the more heat it is going to create. HEAT=HP LOSS
At low HP the loss is low HP wise - but at high HP the load increases and the friction loss goes way up.