Specific SS prop application question please!

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CrazyDave

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I have a 1992 5.7 MC Alpha 1 Gen II. Current prop 14.5 X 19 aluminum, WOT 4300rpm rb2@gr5t50 mph GPS (Cobalt 20'6" BR).

Looking for a little better hole shot to pull skiers, etc. If I drop to a 17P prop with the same diameter, I should see about a 400 RPM INCREASE to 4700. Question: Should I drop to a 17P, but INCREASE diameter to say a 15 or 15.5 to bring the RPM's to around 4600 WOT? Considering a SS for the watersports due to the better performance in this respect.

Finally, will a SS Mercury Mirage Plus 17P x 15 1/2 Dia. (Merc. Part Number 48-18278) work on the Alpha with a new FLo-Torq hub even though it was originally on a Bravo? Thanks in advance.
 
Go to a 14" diameter.

Drop the pitch to 17...rpm's will come up by about 400 which will put you right at the top end where it's optimal for that engine. Your hole shot will be fabulous...will lose a few mph top end.

Bravo props do NOT have Flo-Torq hubs! I'd leave your prop in aluminum. Alpha drives go to hell real fast with stainless since there isn't enough anodic protection. It'll also save you some money!
 
Mike,

Thanks for the advice. I wasn't sure that the corrosion would be an issue on a trailered boat, but I know that SS isn't very forgiving on the gears of an older OD in the event of prop contact. The thought was to use SS in the deep fresh water lake that I typically do water sports, and back to aluminum in the Bay where there's more of a concern with skinny water. I will follow your recommendations on the sizing. Thanks.
 
Dave...if it's a trailered boat,no, stainless is not an issue. I was thinking in terms for a slipped boat. However, your call. ;)
 
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