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How to calculate your top speed in each gear ....in thoery

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MPH = (RPM x CIR) / (gear x final drive x 1056)

that is the math portion, but kep in mid this has no aero factor, no drag factor (as in tire drag/gravity) and no expanding of the tire is accounted for ......

MPH is gonna be your max

RPM is gonna be the rev limiter (lets say 6500rpm)

multiply that by this

CIR is the circumference of the tire in CM *requires more math see the 2nd post* (305/35r18 is 82.8 cm)


take the "gear" aka what the gear is in the transmission (5th in a t-45 is .67)


that by the "final drive" aka your rear end gear (stock for most people is 3.27)


that by 1056 (fuck your coeffcient of 336)

it comes out to 2,313.5904.... ok 2,313.6 is fine

so 538,200 divided by 2,313.6 makes 232.62448 so in theory you could drive 232 and half MPH if you existed in zero drag/gravity

this is very simplified....... im not exactly sober so yeah

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I wish all of this didn't make any sense. I tried working this out in my head while driving on a 2 hour trip the other day... needless to say I got bored and had trouble without paper.

sadly this is without any drag whatsoever! so if youre in space this is for you!!!

i can calculate it as sealevel but yeah it gets crazy from then on ........... this is the simpliest form lol

if you must change 1056 to 336 that will get you closer to earthly point of view ...... its the automotive industry standard for topspeed calculation avoiding hp etc.

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