Homemade Boattail Aerocivic Gets 50 Miles Per Stare

If we learned anything from An Inconvenient Truth, it was that environmentalism starts at home. It's in that spirit that we present the Aerocivic, a 1992 Civic CX with a super low coefficient of drag courtesy of extensive aeromodding. After about 250 hours of work and $400 in supplies, this boattailed Civic achieved a 90-day average of 67.5 MPG (US).


While it may not be the best looking ride on the road, it's hard to argue with performance.

The end result is a car with such low drag that the results of coastdown testing is linear out to 90mph (it coasts almost as well at 80mph as it does at 50mph). I have to get it over 90mph before I start to feel the wind load from high-speed driving. OEM max speed was 95mph. I have had it up to 100mph with plenty of power remaining at that speed (estimated top speed of about 140mph). Wind noise is much reduced from stock. Approximate mileage on a flat road at 85F, 95mpg at 30 to 65mph, 85mpg at 70mph, 65mpg at 80mph, 50mpg at 90mph.
In the future, this rad ecomodder plans to create an adjustable radiator door in order to adjust engine cooling on the fly. [EcoModder ]