SS vs. Aluminum

[Backlash]

In switching from aluminum to stainless steel...should I figure on the same pitch? I currently have a 15x17 aluminum which seems just about right for the current setup. I've heard the diameter doesn't make too much difference (as long as it clears the cav plate). True?
Thanks,
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[Dhadley]

Re: SS vs. Aluminum

A lot depends on what the manufacturer did with the extra or less area of the prop blade. It'd help to know more about your set up and top speed & rpm. But generally speaking you drop down a little going from aluminum to ss. However, if you're willing to work with the set up you might be able to stay with the same pitch. Now, what hull you have makes a huge difference. You just can't make a blanket statement saying "change x inches every time, in all cases".

 

[Backlash]

Re: SS vs. Aluminum

Thanks Dhadley. I've got a 21' Seaswirl WA (about 4500 lbs loaded) with a 1989 Johnson 150. With my aluminum prop I WOT at 5700-5800 rpm with a speed of 43 mph when conditions are perfect. Exclusively used in saltwater.

 

[Dhadley]

Re: SS vs. Aluminum

Good info. If the motor is mounted all the way down now I'd look at something like a standard Stiletto 3 blade in 17 pitch. That should probably allow you to raise the motor some - especially if it's all the way down now. I think you'll be impressed.

 

[Backlash]

Re: SS vs. Aluminum

Yep, it's mounted all the way down. Thanks for the help Dhadley.
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