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mazdaspeed3 - 27 mpg

Join Date: Feb 2008
Location: Georgia
Posts: 8

MS3 - '07 Mazda Mazdaspeed3 mazdaspeed
90 day: 27.85 mpg (US)

speedy3 - '07 Mazda Mazda 3 mazdaspeed3
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Crr

Quote:
 Originally Posted by GenKreton Let's stick to the metric system since it seems to use it, mostly? 1/2C_d is unit-less A in m^2 rho is density, so kg/m^3 v is m/s, so v^3 is m^3/s^3 so we have kg*m^2/s^3 1 N is kg *m / s^2 -> Nm/s 1 J is Nm -> J/s 1 W is J/s, so we are left with pure watts 1 hp is 0.7457 kW Essentially we take the result of the first part and *10^-3 / 0.7457, or multiply by 0.01341. I'm not sure what the second part of the equation is, the addition, but in order to add numbers, the units MUST match. Pmotive=1/2*Cd*A*rho*v^3 is normal for a flat surface. What is Crr1?
Apologies for the long time to respond. Crr1 is the rolling resistance of the tires. Thank you for the detailed formula breakdown. I also looked at the updated spreadsheet boxchain provided. All this information provides a much clearer picture.

Thanks again!
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