prop calculation

[trumanlake]

hwsii after reading the other posts, I have gathered the information you will need I believe. Was wondering what kind of props the formula would come up with for, all round cruise, and top end, with this combination. 1993 Wellcraft cruiser dry wgt 4500 lbs, 60 gal fuel cap, 22 gal water cap, hull length 22' 8", centerline length 24' 3", 8' 6" beam, dead rise 18 deg, merc 5.7, alpha 1 gen II 1.5 gear ratio. Normally run 3/4 fuel, 1/2 water, 2 adults only (just avg size), minimum gear.

 

[junior1113]

Re: prop calculation

put hwsii in your title and he'll get to you sooner. probably going to need to know current prop size and current wot rpms also. will help

 

[hwsiii]

Re: prop calculation

Truman, you didn't give me the model of the boat or HP, so I assumed a 260HP the model of boat I just don't know, so the speed may be off some. Centerline length has many meanings in different public relations terms so I used the hull length and subtracted 1' for waterline length, if the above assumptions are correct the following numbers are right. You need a 17" Pitch aluminum prop to have the correct one for all around cruise.

Boat and Motor

Prop Picker

 

[trumanlake]

Re: prop calculation

Thank you for your time. The marina has a new 15x17 aluminum prop to try. It had a 15.25x15 and with the water almost "hot" (water was 93 deg) I have started to notice a difference in the performance. They also have a 14.?x19 they said I could try if I wanted to. Can't remember if it was 14 3/4 or 14 1/2.
Anyway thanks again, I'll let you know.

 

[hwsiii]

Re: prop calculation

Please let me know your WOT RPM and Top speed for my database.

H