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      02-27-2011, 10:07 PM   #25
aerobod
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Drives: Caterham R500, M2-G87, Macan S
Join Date: Mar 2008
Location: Calgary

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Here is a model of the acceleration profile of a Z4M roadster, with the following parameters:
Air density (kg/m^3) - 1.225
Cd - 0.370
Rolling Resistance - 0.015
Mass (kg) - 1485
Tyre rolling radius (m) - 0.319
Driveline efficiency - 0.830
Frontal area (m^2) - 1.850
Gear Change time (s) - 0.500
Reaction time (s) - 0.200
All gear changes at 8000RPM
Initial launch at 3000RPM with clutch slip
Engine power curve and driveline losses averaged from dyno charts at dragtimes.com

The initial launch is a bit optimistic, as there are too many variables to model the hook-up of the tyres well. This leads to a 1/4 mile time that is a few km/h fast:
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