I need help for my prop size

urnmygto

Recruit
Joined
Jul 3, 2009
Messages
4
I have a 1983 Chap with 305 228hp,Alpha, 18ft open bow.
I have a 21p on it right now and I am turning about 3500rpm, I think this is to big should I go to a 19p? Please help I tihnk I need to be in the 4000rpm range
 

junior1113

Senior Chief Petty Officer
Joined
Jan 29, 2009
Messages
763
Re: I need help for my prop size

a 19 will bring rpms up about 300. i would say 4200-4400 would be ideal. lets first make sure compression test is good and the spark is good to all cylinders. also tach could be off . if everything is good a 17 would bring it up to about 4100-4200. hole shot must suck with 3500 wot rpms. hp is rated at like 4000-4400 so your not getting all of it
 

hwsiii

Commander
Joined
Jan 25, 2009
Messages
2,639
Re: I need help for my prop size

Can you give us the gear ratio and recommended WOT RPM range.

H
 
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