#8000 by Wette Vette
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Location: Valparaiso, Indiana
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Craig or one of you other Motorheads..
How is it that you figure Top speed by rpm, gear ratio, and prop size?
What Im trying to find out is if you have twin 575s and 32 props with a 124 gear, Figure 5500 rpm and 8 to 10% slippage in a cat what does it figure out to be,on the top end?
I used to have the formula but somewhere I misplaced it, can you help me?
Thanks,eliminator219
How is it that you figure Top speed by rpm, gear ratio, and prop size?
What Im trying to find out is if you have twin 575s and 32 props with a 124 gear, Figure 5500 rpm and 8 to 10% slippage in a cat what does it figure out to be,on the top end?
I used to have the formula but somewhere I misplaced it, can you help me?
Thanks,eliminator219
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Here is a way to get the theoretical speed.
Speed theoretical = [(RPM/GR)xPitch]/1056
Speed theoretical= [(5500/1.24)x32]/1056 = 134.41 MPH
Speed 90% Eff. = 134.41 x .9 = 120.96 MPH
What are you doing looking at a Skater!!!
That is about the only hull I know of that will run that good with a couple of 575's. Are you going to the boat show? I will probably go on Saturday. Are you selling your Shorties? If so let me know how much.
Happy New Year!!
Craig
Speed theoretical = [(RPM/GR)xPitch]/1056
Speed theoretical= [(5500/1.24)x32]/1056 = 134.41 MPH
Speed 90% Eff. = 134.41 x .9 = 120.96 MPH
What are you doing looking at a Skater!!!
That is about the only hull I know of that will run that good with a couple of 575's. Are you going to the boat show? I will probably go on Saturday. Are you selling your Shorties? If so let me know how much.
Happy New Year!!
Craig
#10
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Hey Craig, what sort of slippage am I seeing with my 24 OUtlaw. Cruntching numbers at 10% gives me a pretty low number. If I get the correct slipage, I can do some figuring on paper. Thanks, not sure what to do yet on the motor thing. My dyno guy is going to let me borrow a single plane intake, so I am going to Brookeville Lake some nice day in the near future!!!!! I am going to run that intake and borrow some lighting headers and see if I can pick up a few mph. We'll see. That way I will have a better idea of what to do, if anything, other than these ideas. Who said our season is only from April to Oct???!!!
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