Sorry not a math major have read rollout equations over and over.

Ok what pinion and spur do I need for a 2.40 rollout if my tire dia. is

2.40 Thanks for the help as always

Hope this helps

is this a pan car 1:1 or a tranny...

Pan Car Thanks for the help

37 and 116.

Hey guys............have been reading these threads and finally remembered this little program I downloaded quite some time ago. It's pretty simple but VERY effective. You can even open up the source file and input your own gearbox ratios but I think right now I have most of the ones in it you'd need.

Edit...........file to large to upload here.......Click here (www.pennswoods.net/~longbrookers/rcgears111.zip) to download the file. :thumbsup:

pinion / spur x tire size (2.40 in your case) x 3.14(pie)


so 38/120x2.40x3.14=2.3864

this is an easy way to do it with a calulator

Nice little program OvalmanPA!