Originally Posted by Kestrel

The RSX is not aerodynamic. It's front end is way too aggressive and pock marked with holes for style. The air is going to have a great time trying to get around the front end of the nose and make the turn to follow the hood, if it doesn't separate first. Then as the air tries to make its way down the rear hatch it's going to have to make a nice abrupt turn again to follow the trunk line, then separate as it flows of the cliff that is the RSX's rear end. You'll get some nice wake shedding off that which is going to add to your drag. The RSX has aggressive lines running down the side, perfect for adding more separation and wakes. Add on to that that the fact that the undercarriage is exposed (so any air under the car is completely turbulent), the wheels have no dams or covers (so any air that touches the wheels will turn turbulent), there are about a dozen protrusions off the body that will cause turbulence (such as wiper nozzles, wipers, emblems, trim, the antenna, door handles, and side mirrors). If you really want to be aerodynamic you would be almost reclined flat so the car can be flattened out as well.

Nobody would buy a car that is truly aerodynamic because it would be the most uncomfortable thing to drive and horribly inconvenient. And, add to that car manufacturers don't really care about aerodynamics because for the speeds we go at it doesn't really matter. In 2001, GM was beginning to consider adding a full-time aerodynamicist to their body design team for the Corvette. So, yeah, aerodynamics on any passenger vehicle is horrid (the exceptions being specialized vehicles like the Insight, or the EV1).