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Old 12-31-2009, 04:57 PM
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Originally Posted by andrewdoherty View Post
I'd love to hear how you determined that a 17.5 spools to 7k in .1 seconds.

On the bench I have 17.5 motors spooled out to ridicules RPM's, but on the track I find different values due to the load. Just for fun . . .

Lets say your 17.5 12th scale hits 24 mph at the end of your straight with a 3.35" rollout.

24MPH / 60 = .4 Miles Per Minute
.4 MPM x 5,280 = 2,112 Feet Per Minute
2,112 FPM X 12 = 25,344 inches per minute
25,344 IPM / 3.35 IPR = 7,565 RPM

For those mathletes who wanted, by knowing your speed at the fastest section of the track, you can work backwards to the end RPM to input.
Great observation Andrew using top speed is a great way to help determine rpm of the motor which would lead to settings for rpm boost range. I wish I would have pulled my head out sooner and thought of that.
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