[M_a_t_t]

Racing has been a somewhat common topic on here. Since one of the main focuses on this forum is aerodynamics racing and speed are commonly discussed. Aerocivic has disclosed his calculated new top speed, I think it was like 150, somewhere in this thread or on his website.

There is pretty much always a negative pressure in the wake of the car. So maybe theoretically, but in the practical world I would say no.

The semi idea has already been proposed. They also already have flaps at the back of semi trucks for the same reason. I think freebeard has posted the images of the trailer with the inflatable tail. I might be mixing people up though.

The back side of the sphere is curved (naturally) and so it creates lift, which means an even lower pressure in the wake. Thus more drag. Thats my interpretation anyway.

Smaller displacement and not a high performance racing version is typically a good recipe for any car. You just don't ever see a McClaren with a smaller than stock engine. I would say the closest to a racecar with an "eco" trim is the first gen insight, maybe a few other, but mainly the insight. It's pretty light. 1900lbs with battery and everything. Has a pretty low Cd, .24 I think I've read around here. Something you may not be considering is the effect of downforce at speed. The lowest drag would have neutral, no lift and no downforce, the farther you get from neutral the more drag you have.

One of the biggest contributors to fuel economy (when we drive them, not the epa rating) is how you decelerate. I bet if you drove the McClaren in full ecomodder mode (EOC, etc.) you would atleast be close to a smart car. Not the hybrid version, the gasser.