which prop would i need ?

[northendauto420talbot]

hi i am buying a new yamaha 115 4 stroke with a 25" shaft and am putting it on a 1980 starccraft islander that is 22 ft long weighs about 2000 pounds without motor , also iits an aluminum boat , my question is what prop would you recommend for this boat seeing as i have no clue about this i would prefer to stay with aluminum and also i will mianly be fishing with this boat , actually i will be trolling for salmon . any suggestions would be greatly appreciated . thanks

 

[JB]

Re: which prop would i need ?

Howdy, NEA.<br /><br />I would try to get the dealer to help me "prop out" the boat.<br /><br />Start with a 15" to 17". See what rpm you can get at WOT.<br /><br />You want to end up with the pitch that allows the engine to reach, but not exceed the top of its operating range with a light load.<br /><br />If she revs past that, switch to a longer pitch. If she falls short, shorten up the pitch.<br /><br />A general rule of thumb is that each inch represents about 200 rpm at WOT. More pitch = less rpm at WOT.<br /><br />Most dealers will either help you or loan you a prop or two for testing.<br /><br />Good luck.