props and fuel economy

[whipper]

Ya mine has a pad so once up on that theirs very little drag and the motor doesn't work hard at 65-70 and with a big wheel sips fuel. Lower speeds with lots of hull in the water burns more fuel.

[action20]

Lugging a two stroke is never a good idea, for a variety of reasons, but will not accomplish better fuel economy. Props with more blade area (four blades) wil generally get better economy esp at mid range speeds. The real trick to getting good fuel economy with an air entrapment hull is to go fast enough to fly the hull, this reduces the wetted surface and thus reduces drag. You need to define what you mean though---miles per gallon or gallons per hour---for the former, fly the boat, for the later drive the boat at the speed it just planes at, say 25 to 30 mph. I would choose the 26 chopper over the cleaver

I ought to know, been in the prop business for 16 years

Kevin

I agree, my boat at least w my chopper runs effiently at a 25-30 mph range on plane just as he says. Also, the other speed it gets the best mileage / bang for the buck is about 58-63 mph ....packing air under boat at a cruise of 4800 -5200 rpm with some positive trim and Jack plae fairly high ......it's significantly better mpg than almost any other speed other than really slow. It's happy ....not working hard and not a lot of wetted surface , very controllable and fun ! I looked at boat test in magazines on similar efficient Hulls and it's usually consistent with my findings. I agree with not "lugging" I also think that hurts mileage. There are a ton of variables but that's my .02 cents

[Miss Isle]

I can only speak from my experience, running a thirsty v8 outboard, I've found that putting my boat on the pad, like other's have already stated, then backing the throttle off to just where the maximum timing advance happens... on my engine, that's 5000 rpm.

I run a 32 cleaver doing this and it puts me just under the 73mph mark, which is where **** gets real and you have to actually pay attention and drive the boat... With this method, I'm getting just under 3mpg, which from what I understand is exceptional for a v8 looper.

I would assume that most others would find similar results... Most of the time MPG in anything has more to do with the driver than the setup.