what is the horse power lost % between crank h.p to prop h.p
my liberator has 375 h.p at the prop, just wondering what my 502 omc has for h.p. I have a omc king cobra book that shows a 454 with 370 h.p@ the crank, and 310 h.p @ the prop with 60 h.p lost, and a 460 omc king cobra with 340 h.p @ the crank, and 295 h.p @ the prop with 45 h.p lost... it seems that the more h.p the more h.p lost you have. thanks for any help u can give me.

As a rule 10%, some drives may have a little more or less loss.

What kind of GPS speed do you get with your boat? What prop and rpms are you turning at WOT?

i have engine mods done on my boat, my best is 64 mph@5100 rpm the prop I have is 14 1/2 x 20 raker , but I average 63mph...

Is your speed via GPS? If so you have great prop slip numbers!

yes that is gps #s I have my prop out to bblades for some mods, they claim I should be consistant 65 mph. bret recomended the mirage 21 pitch prop I would like to try one to see the diference.

I'm in Onekama and would let you try my Mirage 21 but I'm pretty sure you would need a differnet hub. I'm sending my prop in to Bret as soon as the lake thaws and I can get some base numbers.

Thanks! what kinda gps mph are you getting? I talked to Bret yesterday, I hear he is the man when it comes to props, I've heard nothing but good things about him.

Last summer my best was 64 @ 5900 rpms with a standard Mirage in poor condition. I'm hoping to gain a few MPH going to the Mirage Plus and a few more by having Brett do his stuff.

What gear ratio you running? 1.36?