Mercury 25hp 4 stroke Prop Help

Discussion in 'Prop Shop' started by Tim Gago, May 15, 2018 at 8:13 PM.

  1. Tim Gago

    Tim Gago Member

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    Hello,

    I'm looking to try a stainless Power Tech prop for my setup and could use some assistance. I'm running a 2008 25hp 4 stroke Mercury on a 16' Polar Kraft mod-v hulk with a 20" transom. The hull is about 700lbs. I'm currently turning a aluminum Mercury 4 blade, 9.3 x 9.5 pitch at 5800 rpms. My top speed is about 24mph solo, with a light load. What's my best option to increase speed and possible rpms? My motor is currently raised to the max height possible with a 6" set back. I was reading up on cupping and wondering if I could go up in pitch by going with a cupped prop. Power Tech has a couple model lines, so I was wondering what would be my best option?

    Thanks, Tim
     
  2. Gatorgrizz27

    Gatorgrizz27 I Love microskiff.com!

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    You’re already near the max RPM for that motor of 6000. Going up in pitch and adding cup will both reduce RPM’s.

    Is your bare hull weight 700 lbs, or is it 700 lbs with motor, battery, fuel, cooler, and everything but anglers? If it’s the first, that’s about the top speed you’re likely to expect, it’s just a lot of weight for a 25 hp. Your motor has the same block as the 30, so I’d look at what’s required to bump it up.

    If it seems like you still have too much of your lower unit in the water and it’s dragging and slowing you down, I’d try the Power Tech SRA 3 and jack your motor up.
     

  3. Tim Gago

    Tim Gago Member

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    My hull weighs 700lbs bare. My motor is jacked all the way up, Cant go any higher. Transom bracket bolts are maxed and the jack plate is raised to max. I'm kinda hoping that the 3 blade SRA in a 9 pitch will gain some RPMs and speed. My 4stroke is an EFI and switching to the 30 ECU is a guessing game. Haven't run into anyone yet that's successfully pulled it off.