Best Prop For My Boat

[djrilo]

1st Off, I Know This Is Probably Wanna Of The Most Asked Questions On Here... But Anyways.. I Have a 1976 AMF Crestliner Muskie 550 (Trihull) WIth A 70 Horse Johnson WIth A Short Shaft.... I Run 8 Gallons Of Gas.. And 3/4 Adults. As Of Now There Is A 17P Prop On There Now... Plains out Pretty Quick... But Top End Speed Isn't There... I Don't Have A RPM Gauge As Of Now, So I'm Not Sure where My RPM's Are At WOT.. Nor Am I Sure What They Even Should Be On This Motor??? If I Go To A 19p, On Average, How Much RPMS Do I Drop, Going Up 2 Sizes?? Thanks In Adavnce For Any Insight, Thoughts And Comments...... Safe Boating..................

 

[steelespike]

Re: Best Prop For My Boat

Pretty sure the 70 was only available in a 20",long shaft.
what is the diameter of the prop.Measure from the center of the bore too the tip of as blade
and double there result.Or look under the prop nut.Do you know if its a small or large gear case?

 

[djrilo]

Re: Best Prop For My Boat

Pretty sure the 70 was only available in a 20",long shaft.
what is the diameter of the prop.Measure from the center of the bore too the tip of as blade
and double there result.Or look under the prop nut.Do you know if its a small or large gear case?

thanks for reply..your right it is a longshaft..... I Will messure the prop shortly and get back with you on that..thanks for your fast reply.....