Amateur Aerodynamics

 There is a list of “65+ Efficiency Mods” on the Ecomodder website, a sticky at the top of one of the subforums. Some of the suggestions are engine- or drivetrain-related, but a fair number are aerodynamic. These range from removing roof racks to fitting solid wheel covers to building the full “boat-tail” that Ecomodders are sort of known for now, mostly through the efforts of one forum member who originated the Aerodynamic Streamlining Template (I’ll call it the “Template” from here on) as the cure-all for every aerodynamic problem. I decided to implement some of the most popular modifications on my 2005 Civic, in addition to some of my own such as removing the power steering system. I took off the exterior mirrors and bolted small convex mirrors to the sail panels inside. I blocked off most of the cooling air intake in the front grill, first with sheet metal and then with spray foam, shaped and fiberglassed to give a smoothly rounded front with a small inlet duct sized just l...

Nearly a decade ago, in the days of the Great Recession gas price shock, I found myself facing a conundrum: I had a very long commute, more than fifty miles each way; I had a reasonably efficient 2005 Honda Civic EX that returned mid-30s MPG; but I was still spending more than I wanted to on fuel. Was it possible, I wondered, to modify my car in such a way that its fuel economy would improve? I still have a fondness for 7th-gen Civics, logic be damned. I wasn’t the only person asking this, of course. Every time gas prices rise a slew of news outlets and blogs are more than happy to publish articles on getting the best gas mileage out of an existing car. Advice tends to range from the basic but useful (e.g. clean out your car so you aren’t carrying around extra junk all the time) to outright falsities (wash and wax it to reduce aerodynamic drag). I was interested in something more. I didn’t keep unnecessary items in my car, I kept close to the speed limit, I grouped errands together s...