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Author Topic:   Gears & RPM's
posted September 09, 2003 05:48 PM
i would guess around 550.

mistyped the first one..meant 550 not 350.

[This message has been edited by dirtbuster (edited September 11, 2003).]

posted September 09, 2003 06:48 PM
go to the toolbox and use the rpm calculator to get a pretty good idea. It will vary some due to track conditions and such but it will give you an idea.

posted September 09, 2003 07:23 PM
Depends on the track size and surface. Based on my area, I would say 700-900 rpms.

posted September 11, 2003 12:18 PM
Mathmatically this is really easy guys....

Take the new ratio and divide by the old ratio to get the % change - then use your current RPM's and multiply by the result...

So say you're running 6000 RPM right now with the 5.43, and you're going to switch to the 5.83

5.83/5.43 = 1.07366, (or about 7%) - multiply that by the 6000 RPM and you get 6441 RPM to turn the same "speed"

Of course the reason you're doing this is to get the engine into a better area of the power band, so the net result may be more RPM's or less RPM's depending, but the calculation will get you a direct relation to MPH for the effect of the gearing change