Posts: 3508
Location: Elk River, Minnesota | Hiya,
It is a start. First off, my guess is that the bigfoot motor should be topping out at 5500 rpm when you are lightly loaded. With that in mind, my guess is the boat may not pop up on plane really quick, but it gets there. My gut instinct without knowing anything further would be to say drop to a 13 pitch prop for aluminum, which will help your rpm's, and really give you that low end torque that the bigfoot is designed for. You should be able to get up on plane quickly. From there, if you can go a little smaller on diameter do so, and if the motor is flat on the transom, raise it up two bolt holes. Going steel would lower your rpms by about 200 - 300 rpm in the same pitch so by going down 2 inches in pitch, you will be on the positive side by about 200 rpm as each inch of pitch is roughly 200 rpms (steel = -200, down pitch 2" = +400), Each bolt hole you raise the motor will increase your rpm by about 100 rpm, so if you go up 2 holes, you will gain the 400 rpm you need to get you close to optimum running.
The boat will not be a speed demon by any means, but 33 - 35 would be in the ballpark depending on where your motor is mounted and the prop you choose to go with.
As for props:
**Michigan Ballistic would be a top choice. This prop is designed with heavy tip and trailing edge cup along with rake to raise the entire rig on the water.
**Michigan Rapture will be a little thicker, is vented for hole shot, and will be a bit smoother at the top end. Very strong prop for overall performance.
**Mercury steel props would be good as well, although selection of design will be limited to something similar to the aluminum props. Not much to be gained here other than durability.
**Solas Titan: Another prop built for overall performance, but not as strong of a prop as a rapture or ballistic.
The best thing you could do is find a dealer with a prop demo program (blue props) and go test various pitches and diameters. Track your results on hole-shot, rpm, slip, speed, etc. and determine which is working best for your rig. One will stand out among the others...
Steve
Edited by VMS 4/23/2014 1:21 PM
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