Merc. Alpha aluminum to SS

Drowned Rat

Drowned Rat

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I've got a 17' bow rider with a 135hp mercruiser. On it right now is a 14.5 X 19. I've got my eyes on a SS prop on craigs list that's 23" pitch. Is this going to be too much for my boat? Right now my hole shot it good, even better since I just put on Smart Tabs, and top end is right at 40MPH with a moderately light load. It pulls skiers well. Will it still pull skiers okay? Thanks for any help you can offer. :)
 
WillyBWright

WillyBWright

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Re: Merc. Alpha aluminum to SS

It all depends on what RPMs your are turning now, but I'd bet it's too much of a jump anyhow. Especially for towing. It could be repitched an inch lower, but even then...
 
Drowned Rat

Drowned Rat

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Re: Merc. Alpha aluminum to SS

Thank Willie. I'll pass on it then. What size would you call "ideal" for my situation so I'll know what to keep a look out for? Thanks!!
 
WillyBWright

WillyBWright

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Re: Merc. Alpha aluminum to SS

You typically go up a size when switching to stainless. Say from a 19 to a 21. But to keep it good for towing, I might aim for a 20. Stainless also tends to come in even numbers while aluminums are odd. But that's way from carved in stone. If it's a ventilated stainless, it'll need plugs for the vents.
 
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walleyehed

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Re: Merc. Alpha aluminum to SS

Normally, we don't go up in pitch when going to SS..due to the more efficient design, we usually go DOWN because the SS will pull harder.
99% of the time, this will be the case unless you have a real dog of a prop now that has basically no lift.
 
Drowned Rat

Drowned Rat

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Re: Merc. Alpha aluminum to SS

Thanks so much for the advice. It sounds like if I stick with the 14.5X19 that it should work well.
 
Z

zeezer

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Re: Merc. Alpha aluminum to SS

walleyehed said:
Normally, we don't go up in pitch when going to SS..due to the more efficient design, we usually go DOWN because the SS will pull harder.
99% of the time, this will be the case unless you have a real dog of a prop now that has basically no lift.
Click to expand...

I agree with walleyhed. Aluminum to stainless means lower pitch. I went from 21p Aluminum to 19p stainless. Better hole shot, higher engine rpms, faster top end. you may want to go to a 17p stainless.
 
JUSTINTIME

JUSTINTIME

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Re: Merc. Alpha aluminum to SS

the new aliumium props are much different material now
ask tom clark on the hull truth or propgods.com
 
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