Reconsidering

[todd brinkerhoff]

Remember, your props are designed for a planing hull, meaning they are smaller with greater pitch, than you would see on a displacement hull. If you switch the props, you will probably then need to look at a strut, and possibly larger shaft. I think the distance from blade to hull needs to be in the 20% range of your diameter.

I don't know if this is possible, and I'm sure someone can answer the question, but can you change the gearing in your current gearbox set-up? I know these gearboxes came with a bunch of different reduction ratios.

[prowlersfish]

Gear cannot be changed on a 1 to 1 (no reduction gear on a 1 to 1 ) yes a larger shaft will be need for a reduction gear .

Currently that boat should have a 14x10 or 14x11 or something close to that I believe

[CrunchyBacon]

I did finally find the prop recommendation for the boat I want to build. It recommends:

Quote "The weight of the engine should be kept to a minimum for best performance, however engine weights to 1500 lbs. are acceptable. Either gasoline or diesel engines can be used. The engine drives through a straight shaft with transmission. The 3 blade propeller is 22" maximum in diameter; the propeller shaft is 1 1/2" diameter."

It doesn't specify the pitch but I'm sure that depends on the motor being used. As to little pitch will cause the engine to over rev and to much pitch will lug the engine.

[ready123]

A diesel engine might well be able to drive a square prop... 22x22.

[RWS]

wonder what it will cost to scrap the donor boat hull?

RWS

[todd brinkerhoff]

Dream killers I tell ya..

Actually I do have a question...how to you prop a displacement hull? Do you prop it for wot at the hull speed? This hull seems like it would go faster than hull speed.

..and with the right reduction, you can turn 22's with gas. My boat turns two 22X22's....I can make you a deal on one of them....

[RWS]

so many choices.....

each one an expense

and an EXPONENTIAL expense if it is WRONG and has to be changed, corrected , or redone.

Despite doing a successful repower, personally, I would not have the grit or pocketbook for such an adventure.

I appreciate the KNOWN vs. the UNKNOWN.

RWS