Best prop size for a Suzuki 115 on a 20' boat?

[billh1963]

Hi,<br />I'm finishing up the restoration on a 1974 Aquasport 19-6 and am installing a used 2001 Suzuki 115 2-stroke. The hull weight is 1500 lbs and adding engine, fuel, etc. will take me up to around 2500 lbs. The engine currently has no propeller so what diameter/pitch would give the best cruising speed/fuel efficiency? I won't be pulling skiers...just running from fishing spot to fishing spot.<br /><br />Thanks!

 

[phatmanmike]

Re: Best prop size for a Suzuki 115 on a 20' boat?

a 19' boat and a 115hp, youd probably wanna start with a 17p prop, 3 blade, stainless if its in your budget.<br /><br />maybe even a 15p. thats a slightly small motor for that size hull. i have a 20' mako and a 200merc and i have a 20p 3 blade stainless and i get 56-5700 rpms at WOT and 54mph

 

[billh1963]

Re: Best prop size for a Suzuki 115 on a 20' boat?

Thank you for the reply. I do plan to buy a stainless prop.<br /><br />Does anyone know what the OEM size would be?

 

[Dhadley]

Re: Best prop size for a Suzuki 115 on a 20' boat?

I would try something in the 17-19 range. With your 2:1 gear ratio it works out to almost the same pitch as a larger motor with the 1:86 ratio. And naturally a larger motor swings more diameter too (14 1/4 vs 13 1/4).<br /><br />Count your propshaft splines and shoot me an email (dhadley50@aol.com), I have an idea I'd like to run past you.

 

[Dave Abrahamson]

Re: Best prop size for a Suzuki 115 on a 20' boat?

I have a 115 Johnson on a 20.5 foot Angler CC.<br />I run a SS 12 3/8 X 17P and get about 5600-5800RPM @ 36MPH. Not gonna win any races, but I get to my fishin' holes and back just fine. <br /><br />Good Luck and definitely take up Dhadley on his offer of help.<br /><br />Dave

 

[billh1963]

Re: Best prop size for a Suzuki 115 on a 20' boat?

Dhadley hooked me up with a prop that should work great.<br /><br />Thanks everyone!