Benchmarking the 20 footer
 

I hope to test the 20 footer with a 13.25 x 15 plus hydroshield, then without, then with no hydroshield and a 13 x 17. Will report back. Yamaha F100 power. Non ethanol gas. No tabs, no T-top. I know the first setup is 28 knots or 33MPH. Awesome hole shot and planing. I know the 13 x 17 is no faster and poor hole shot with the hydroshield.

Fishstretcher, make sure you note the prop make and model. As you know the different shapes do different things. Are you using one of the Solas props now?

Yeah. Amita 4 for both. Aluminum.

I did hold plane at under 10 knots (9.5)with the hydroshield and 13.25 x 15 prop. 31MPH with two guys and full tank. 5800 RPM

I haven't had a chance to benchmark it yet- some family stuff in the way. But I did verify 5.0 nmpg/5.7mpg for island trips in buzzards bay. 19-20 knot cruise at 4500 RPM, pretty much exclusively. 2 guys, and a few hundred lb of gear on board. That was a 70 mile average. Of which, 12 nautical miles are at headway speed.

Ha. Singlehanded gets worse mileage. 61 nautical miles and 13.2 gallons. That's about 4.6 nautical miles per gallon. With a little umbrella rig trolling and hammering into a crappy buzzards bay quartering chop at slightly slower cruise like 17-18 knots. That might explain it.

Be sure you have the motor set high enough and your not dragging the foil - if its the correct height it will plane at lower speeds as well - with an Alum prop prolly 1" above the hull bottom at the cav plate

It is a hydroshield- Fr. Frank turned me on to them. It is under the prop, so it is first in the water and last out. But the anti-ventilation plate is up out of the water on a hard plane, I think.

I don't know of anyone planing at below 10 knots? At least when i trim right. I think I am doing well?

At 80% trim up, I blow out and hit between 5900 and redline. At 50% trim, I hit 5800 RPM. At 20% (80% down), I am at 5700, so I think I am pretty good. Redline is 6000.

It looks like I am at 9-10.5% slip at WOT slogging the hydroshield thru the water. 28.0 knots on a 13.25 x 15P 4 blade. Assuming it is 15" pitch on the nose...

I never got to try pulling the hydroshield. Maybe later this year.

Sounds pretty good overall, 10 knots is dreaming your right - try and figure out what you have