Prop Rule of thumb to raise rpm by 500 rpm ?

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07-30-2021, 03:30 PM

#11

F-2 Speedy

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still doesn't work, maybe its a cookie thing or ad block, but Im not getting any warnings

07-30-2021, 04:30 PM

#12

Donzi Z22

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Quote:

Originally Posted by F-2 Speedy

I cant seem to get this to work for my boat, do you populate the first 4 entries then click calculate ??

Try filling the first 4 then 6 then calc slip. Then you can play around with the numbers

07-30-2021, 04:41 PM

#13

F-2 Speedy

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got it working, fill in the first 3 then actual speed..............8% @ 92 theoretical 98

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SB (07-31-2021)

07-31-2021, 07:55 PM

#14

smokediver

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Quote:

Originally Posted by Donzi Z22

I changed my drive from a 1.62 running a bravo 1 26 pitch at 5000 rpm at 62 mph. Now I changed my drive to a 1.47 and the 26 is to big a wheel.
I only get 3800 and 52 mph.
With the 1.47 I need to re prop to get back up to 5000. I need to gain 1200 rpms. Ideas ?

I changed ratios in my old 16 classic. It ended up being 4 inches of pitch .. if you were turning a 25 you would need to drop to a 21.