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Old 02-12-2012, 07:43 AM   #162
Deslock
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Join Date: Oct 2009
Drives: 2013 DZE/01 (sold for MX5 ND1)
Location: western MA
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Quote:
Originally Posted by serialk11r View Post
How did you add drag in? CdA 1/2 \rho v^2?
1/2 * VFA * CoD * rho * V^2

rho varies depending on temp, elevation, etc but I used 0.00235 slugs/ft^3

Quote:
Originally Posted by WingsofWar View Post
looks like only Cd was used not CdA.
I used VFA of 23.68 ft^2 for the WRX (found from google) and approximated the BRZ as 20.5 ft^2. I think the VFA I initially used for the BRZ was a bit too low, so I changed it and added more notes to the plot.

I used this WRX dyno:
http://www.clubwrx.net/forums/engine...yno-pull.html:

I know nothing about rolling resistance, but I based my numbers on the formulas I found at http://www.mayfco.com/aero1.xls which was discussed at http://www.rx7club.com/showthread.php?t=541682

Other links:
http://www.miata.net/garage/tirecalc.html
http://www.mayfco.com/mazda.htm
http://www.engineeringtoolbox.com/ca...on-d_1309.html
(I used the last two linkes to make sure my numbers were in the right ball park)
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