Re: "So someone decided use different battery size for Model 3 "
ViM offered "frontal area determines drag"
'Determines' isn't quite the correct word. There are other parameters, such as Cd and V^2.
My largish W211 Mercedes supposedly has a Cd of 0.26. On the other hand, the V^2 can get pretty extreme at times.
Biting the hand that feeds IT
