Prop questions

[CTD]

I have an 18.5 ft boat 4.3 OMC with a 14 1/4 x 21 prop that runs at 4600 rpm, 45.7mph gps. I might want to pull a tube or single skier someday but for now I fish and just enjoy the water. I want a spare prop and have been watching e-bay. Questions<br />If I go stainless do I get the same size or a bigger pitch, would a 14 1/4 x 23 be too big?<br />Does a stainless weigh much more than aluminum thus putting more strain on the outdrive when shifting or is it not noticible<br />If I go to a 14 1/2 x 19 would that be the same as what I have as far as preformance goes. <br />If I wanted a 4 blade prop would I get the same size or smaller dia or less pitch<br />Do the replaceable hub props absorb stress as well as the oem type<br />Thanks for any information you can provide

 

[LubeDude]

Re: Prop questions

The general rule is if you go from aluminum to stainless with the same diameter and pitch is that you will lose about 200 RPM because of the weight and the lack of flex in the stainless prop.<br /><br />Yes, a 23P in a stainless would be too big.<br /><br />If you go to a 19 in a stainless, you would likly be were you are now, but would probably pick up a mile an hour or two in WOT speed. If you want more out of the hole and pulling power for pulling tubes and such, I would say a 17P in a SS would be about right.<br /><br />The hub design doesnt matter IMHO. The resale on a replacable hub prop is generaly better do to the fact that it can be made to fit anything almost.<br /><br />Walleyehed is the Prop Guru, he should chime in eventually.

 

[walleyehed]

Re: Prop questions

Changing diameter by 1/4" won't change things alot.<br />Going to Stainless has advantages that far out-weigh the disadvantages involved.<br />A Stileto 3-blade would be most likely the best all-around choice. The TurboI would be a good option as well.<br />Personally, I would stick with a standard, factory-type hub arrangement.<br />The SS prop does weigh more, but there are other items that come into play when shifting, and the SS prop will have the rubber hub insert just like an aluminum prop.<br />As for a 4-blade, alot depends on the style of prop you are running now.<br />There are no rules set in stone on going to a 4-blade, but I'd say stay in the same pitch range as what you have. One size lower in pitch wouldn't hurt with the specs you give.<br />Best advice is test, and test agian.