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capecoddonzi
07-13-2012, 01:19 PM
Hi, what is the best prop for my 22 classic, re powered with 355 sbc, 425hp, bravo 1, all around performance prop, then a top speed prop, it's a lake boat now, thanks, Gary

osur866
07-13-2012, 01:25 PM
You'll get several opinions on this, but if it was me I'd start with a 25P M+ or turbo if it's a 1.5 ratio Bravo and making a true 425HP and that'd give a good starting point, the best for you may not be the best for me, gonna depend on what your driving style is and how you plan on using your boat, test some props and just keep trying them til ya land on one that fits your needs

Ghost
07-13-2012, 01:58 PM
Do you know enough about the motor to know what RPM gives your peak of 425 HP? (AKA, are you trying to spin the usual 4800-5000, or are you needing to be up to more like 5600 to use all your HP, or what?)

capecoddonzi
07-13-2012, 03:11 PM
[Motor has solid roller cam, will twist 6000 all day, gill exhaust, and so on, im looking for top speed, it has the 19pitch 260 merc prop on it now, 57mph at 5700rpm, need speed up and rpm down, so I have a 14.6 23 pitch to try and couple of 21 pitch cleavers, again, thoughts, thanks, Gary

MOP
07-14-2012, 06:29 AM
IMO a 25 is a little to aggressive, I am running a 383 about 400hp in my 22. The 383 makes a bit more torque I am turning a 23" Turbo 4 blade @5k giving me 65.5. The cleavers do not do well on a 22 they give stern lift, stern lift is the last thing a 22 needs. 22's like a lot of trim to get the bow up, a bow lifting prop is a much better way to go.

Ghost
07-14-2012, 11:32 AM
Apologies if I missed something, but do you know your target RPM for WOT running? (While it's good that your motor will turn 6k, it sounds like you are actually aiming to run wide open somewhere below 5700, maybe well below it.)

Presumably, your peak HP occurs somewhere between 4800 and 6000. Just curious if you know where that peak is, because in theory, your max speed would occur near there with the right prop.

I think the props you have will be useful to try--certainly should give you some more data to work from at least. Based on your results with the 19, like MOP, my guess is that the 25 will be too much pitch.

What's your drive ratio? (We're so used to seeing 1.5s that we sometimes assume, but your #s above make me wonder if it's a 1.65.)