Re: Is 42Mph Right?
A couple of observations/questions:
1) define "downstream". How much current do we subtract from the 42 MPH?
2) A 225 at the flywheel, if everything is right, is only 190 - 205 at the prop as they rate them today. So your buddies 220 4.3 has as much as 30 more hp at the prop and it is lighter.
3) I think I have confirmed a 1.61 ratio. Do we know that this drive is a 1.6?
4) I am getting 6% slip which is very good, going the wrong way as we are looking for improvements.
5) The WOT range is 4000 - 4400, so if all else is right, going up in pitch is not the answer.
6) You said "about 4000". Can you confirm what it was exactly? You used the inductive tach properly? Both tachs agreed I assume.
7) What're you doing as far as trim etc.?
8) What's your typical load like? Stuff, people, ice, beer etc.
I feel like something isn't right, but having a hard time pinpointing. Anything else will help. I am thinking it should pull a 21, but the data says it won't.
1. Downstream in the slow moving Allegheny River north of Pittsburgh, Pa.
3. It is in fact 1.6 ratio
6. I use my inductive tach very often, and I am familiar with the proper set up and operation. The highest RPM recorded was 4053. The tach in the dash should 4000 on the nose, so Its pretty close.
7. Trim is set in the center hole on the transom shield.
8. This info was gathered, with just myself in the boat, no coolers, just safety equipment, ropes, 2 15lb anchors, one pair of skis. Btw, I weigh 300lbs. One battery, small tool box with a few screwdrivers, a few combination wrenchs, and a roll of duct tape. Nothing extra at the time of testing. I know I can pull a few more RPM, and still hold together. Besides, I am not usually running her WOT, 4bbl's screaming, etc. Just want to make sure I am getting everything out of her. BTW, the timing is set at 10 btdc, and the advance is working, no weights seized up or anything.
