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donee · 12-17-2009, 08:33 PM

Hi All,

The EPA may have a new test methodology, they are talking about. Remember, the main reason the Car companies make these measurements is they are required to by the EPA. Why? So the CdA factor can be dialed into the dynamometer settings to simulate air drag in the mileage/polution testing.

Its quite probable the EPA now has Yaw conditions required for the testing, and then they average the whole thing down to some confusing combination of straight and twisted air drags. Kinda like the EPA does with the highway and city mileages...

12-17-2009, 08:33 PM	#65 (permalink)
donee EcoModding Apprentice Join Date: Jan 2008 Location: Chicagoland Posts: 204 - - '10 Toyota Prius III w/Navi Thanks: 4 Thanked 12 Times in 12 Posts	Hi All, The EPA may have a new test methodology, they are talking about. Remember, the main reason the Car companies make these measurements is they are required to by the EPA. Why? So the CdA factor can be dialed into the dynamometer settings to simulate air drag in the mileage/polution testing. Its quite probable the EPA now has Yaw conditions required for the testing, and then they average the whole thing down to some confusing combination of straight and twisted air drags. Kinda like the EPA does with the highway and city mileages... Last edited by donee; 12-17-2009 at 08:44 PM..