There is substantial room for aerodynamic improvement in the Insight. The AeroCivic achieved a Cd of 0.17 by streamlining a Cd=0.34 '92 Civic hatchback. I believe it will be possible to achieve the same or better shape (Cd=0.17, 32% reduction in highway fuel consumption, plus extending lean burn) with an Insight with less effort and shorter overall length, and I intend to do so. Here's a rough sketch of what I have in mind. It's 95cm longer than stock, which makes the car as long as an Accord.
The rear truncation is as tall as a US license plate, and leaves room for a few lamps on either side.
When a 16" tail cone was fitted to the GM EV1, the drag coefficient dropped from 0.167 to 0.153. (
source)
Btw, is anyone here good with OpenFOAM?
