Excel top speed calculator
#1
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Excel top speed calculator
i made this because i was bored, and because i wanted to know my top speed not my rollout. i think i got it right, so if theres anything wrong tell me.
btw its defaulted to an 'out of the box' HPI E10. and as it says, only edit the yellow cells or you'll break it
if you have no internal gear ratio, then set it to 1.
Joe
p.s i added an extra unit of speed for all you speed freaks!
btw its defaulted to an 'out of the box' HPI E10. and as it says, only edit the yellow cells or you'll break it
if you have no internal gear ratio, then set it to 1.
Joe
p.s i added an extra unit of speed for all you speed freaks!
Last edited by joe of loath; 12-20-2007 at 02:28 PM.
#2
from what I saw, theres no Pi in your formulas anywhere, and your overall gear ratio needs to be spur/pinion * internal gear ratio.
you can fudge aerodynamic drag by multiplying by .95 or .8 or pick a number less than 1, or you could figure out/find the formula for drag
good luck
you can fudge aerodynamic drag by multiplying by .95 or .8 or pick a number less than 1, or you could figure out/find the formula for drag
good luck
#3
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hmm strange, it seems to work..... i know, i should replace diameter with circumfrence.
#4
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from what I saw, theres no Pi in your formulas anywhere, and your overall gear ratio needs to be spur/pinion * internal gear ratio.
you can fudge aerodynamic drag by multiplying by .95 or .8 or pick a number less than 1, or you could figure out/find the formula for drag
good luck
you can fudge aerodynamic drag by multiplying by .95 or .8 or pick a number less than 1, or you could figure out/find the formula for drag
good luck
oh and aerodynamic drag is exponential (or is it squared or cubed) anyway it isnt linear....
EDIT: a bit of trial and error later i seem to have my internal gear ratio sorted, but still no formula... it works as logn as you know it!
EDIT: it wont work.. somethings wrong :'(
EDIT: ok i got it working! there were some relics in the equations from when i was working in millimeters.
Last edited by joe of loath; 12-20-2007 at 12:59 PM.
#5
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ok it seems to work now.
btw this is just a bump TTT
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EDIT: now changed tyre diameter into MM from meters
btw this is just a bump TTT
^
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EDIT: now changed tyre diameter into MM from meters
Last edited by joe of loath; 12-21-2007 at 02:17 PM.
#6
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bump, just in case someone actually cares.
p.s. IT WORKS!
p.s. IT WORKS!
#7
anybody got an idea of the RPM of a 4.5R brushless motor?
#9
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