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14pitch

12%v-drive gear

5100 rpms

thanks

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567 Posts

14pitch

12%v-drive gear

5100 rpms

thanks

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1,640 Posts

send me your email and I will send you an spreadsheet

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284 Posts

You'll be suprised how off those calculations really are.

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Which calculations??

You'll be suprised how off those calculations really are.

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3,359 Posts

7100 rpm x 1.18

8378 rpm x 1.25

10,472.5 x 60

628,350 divided by 5,280 (feet in a mile) = 119.005 mph

119 mph x .85

Jocko

Applied to your info provided;

5,100 rpm x 1.12 = 5,712 x 1.166 (14 pitch) = 6,660 x60 = 399,600 div. by 5,280 = 75.68 mph

75.68 x.80 (

Jocko

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Agreed. Especially when you are entering number you don't actually know.these ones

The excel spreadsheet I use is just the simple calculation Jocko was talking about.

But it does have the variable of the slip. You need to back it up with a gps, you can then figure out your boats "Slip" you can then see how changes effect the efficiency of the boat.

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No matter how close you dial in your calculations with the slip and everything, its still gonna be off.

My cents is all

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The calculations / formulas are

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Well I can't say for sure since you didn't say what type of boat but it should run some where in the range below depending on the actual slip. If this is your TR-2 I'd say 108mphOk. Here's a test:

11x16 prop

22 gears

7100 rpm.

What's the speed?

RPM Gear Pitch MPH(T) MPH(P) Slip

7100 1.22 16 131.1 104.9 20.0%

7100 1.22 16 131.1 106.2 19.0%

7100 1.22 16 131.1 107.5 18.0%

7100 1.22 16 131.1 108.8 17.0%

7100 1.22 16 131.1 110.1 16.0%

7100 1.22 16 131.1 111.4 15.0%

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Thanks everybody for the info!!!!

Tony

Tony

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Depending if your still accelerating or leved off I'd guess about 127-128mph depending on slip (I guessed 18%).How about

Cole TR-2

7500 rpm

11 by 16 RB prop

37 gears

How fast do you think, I did the calc. But imagine going that fast. So I want to see what you guys think.THS BOAT

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I have some formulas I use to claculate with but there's so much varience in set ups, driving styles, props and gearing it doesn't work well unless I have a baseline number for the particular boat and driver. My calculations show [email protected] but aren't you running NA? seems like the gear is a little high and the rpm is a little low for an NA piece to be really quick. I would think it would be plenty quick enough for TE though. Once you get some numbers I could rerun the calculations with your numbers.

BTW Good Luck, beautiful boat you built there! devildevil

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