10% faster for $100

[FishStretcher]

Now that I am a little less of a Seacraft newbie, I thought I'd repost some wisdom that was handed down to me by the guys on the board who really know boats.

When I got my boat- a 20 foot master angler- I immediately repowered it with a Yamaha F100. It is lighter than the 2 stroke Yamaha 175 that was on it, but only by about 40 lbs. And the F100 is known for being a low torque high revving, but efficient motor. With the help of Fr. Frank, I purchased a hydroshield- a delta wing that flies under the skeg. It helps you play safely in shallow water and helps with low speed planing. But at the cost of more drag and a bit of top speed. With it, I can plane at about 13 knots singlehanded with the 60 lb kicker and the F100 on the transom.

With a 12-3/4 x 17" four blade aluminum prop, that is. The prop is supposed to help you plane by providing lift, too. But with that prop I was pulling 26 knots (30MPH) at 5600 RPM, and a bit less with a full crew.

I didn't like the performance out of the hole and wanted to spin the motor a bit faster, so I started experimenting. I moved the motor up a notch. Now it has the *anti ventilation plate* (forgot to add this earlier) between 1 and 1-1/2" above the keel. It was previously just above the keel. That was worth probably 150 RPM and almost 2 knots, and was free, less a tube of 3M 5200 adhesive. (I have a hoist, and do my own work). The motor couldn't go higher though, as it would blow out in turns if I didn't trim properly.

Then I changed to a 13 x 15" 4 blade aluminum prop. That allowed me to pull to redline (6000 RPM), and the boat *jumps* on plane now. Plus it picked up about another knot in speed.

I am sort of a discount boater and I fish up against the shore, so I have never had a stainless prop. I suspect with more prop tweaking, there is more to be had, or by changing to a top water anti ventilation plate wing, there might be 2 more knots in it, but I haven't had the money or time to try yet.