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      09-01-2008, 10:08 PM   #1
rzm3
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Drives: E92 M3
Join Date: Aug 2007
Location: USA

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Arrow M3 Theoretical Top Speed Calculated

Update 2:

Question: why does BMW limit its cars to 155 mph intead of unlimited?

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Update 1:

Recalculated using frictional losses derived from a 320i coupe. Total frictional loss, which includes transmission loss, tire resistance, etc., adds to about 30%.

The updated top speed is 183.62 mph.

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Assumptions:
front wheel rolling losses not included (since power at wheels are found from a dyno, where the front wheels are stationary
Air density at standard sea level used
factors from gear ratio neglected

Result:
with a transmission loss of 13.29%, the M3 is capable of reaching a top speed of 196.95 mph.

Method:
when power generated by the engine equals the power induced by drag force, the car cannot accelerate anymore and thus reaches top speed.

Let me know if there is anything I can modify to make the calculation more sound.
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2011 E92 M3 DCT
1991 Spec Miata
2008 E92 M3 DCT - KW Competition 2-way / Brembo 365 BBK / OMP ARS racing seats / rear seats delete / GT4 aero / AiM EVO4 data logger / SmartyCam racing camera
2008 E92 M3 6MT
2008 E92 335xi

Last edited by rzm3; 09-03-2008 at 12:00 AM.