What prop...?

[Valmet412S]

Hey guys, just joined the forum and looking for a little help. I just put a 150 VMax and 6" Hi-Jacker on my Sprint 286 Pro Tourney. The motor came with a 21 pitch stainless prop by Michigan Wheel. I know I am going to be under-pitched.

With the 150 Evinrude I took off, I ran a 24P Raker to 69mph (speedo) with a light load and no jack plate. RPMs were good and prop shaft was over 4" below lowest part of hull. The boat would porpoise (sp?) very bad and I had to trim it WAY up to get past that. The end result was a massive rooster tail.

With the jackplate and the Yamaha, the prop shaft is now right at 4" below the lowest part of the hull, with plenty of room to come up. Any ideas on what prop I should look for?

 

[NHGuy]

Re: What prop...?

Do you know the gear ratio in the lower unit? With the jack plate and a better although similar HP motor you should be able to go to higher speeds with out all the rooster drama. Start out with the cavitation plate just a little lower than the bottom of the hull. Just watch out for prop blowout when you trim up, you don't want to over rev the motor. As far as prop, try the one you have and adjust from there, it's got to be too short though!