Going by the Cd alone is a rough estimate; but it is the most important piece. The area is divided by the Cd, so the change in area has to be 3-5X greater than a change in Cd.
So, we could do some area calculations based on the known dimensions of the i MiEV vs the CA-MiEV. The i MiEV is probably taller, but narrower than the CA-MiEV; but they both are big enough to have two adults seated side by side, in relatively upright positions.
I know to a very precise level what the frontal area is for my CarBEN EV5 design (because I have the CAD drawings) and it is 25.1 square feet. Comparing this to the two Mitsubishi cars:
i MiEV dimensions:
Quote:
Width 1,475 mm (58.1 in)
1,585 mm (62.4 in)(US) (excluding side-mirrors)
Height 1,600 mm (63.0 in)
1,615 mm (63.6 in)(US)
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This is 27.56 sq ft - but the actual frontal areas is less, because of the wheels and the sloped sides and curved roof, etc.
Here's the EM CdA list:
Vehicle Coefficient of Drag List - EcoModder
From that list:
Quote:
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Mitsubishi I 2012 - [Cd]0.35 [H]63.6" [W]62.4" [A]23.2[sq ft] [CdA]8.10[sq ft]
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The frontal area is ~15.5% lower than the HxW number.
The CA-MiEV is 1550mm High x 1775mm Wide = 61.02" x 69.88" W = 29.61 sq ft. - 15.5% = 25.02 sq ft So, the CdA of the CA-MiEV is 6.50 sq ft.
Even though the frontal area of the CA-MiEV is 1.8 sq ft (7.25%) greater than the i MiEV - the Cd of the CA-MiEV is 0.09 (~26%) lower.
The CdA of the CA-MiEV is 1.6 sq ft (19.5%) lower than the i MiEV.
The Cd is the most important factor in comparing cars, in my opinion.