Started thinking about this midway through construction of my first air dam, and thought about it as I removed it.... and continued occasionally modifying my plans over about a year or so now. Finally got a day to dump into it, and got it started. Did take some changes to my original plan; bummer but still should work great.
Goals for this mod:
•Improve by +3 mpg highway (less than 10%) vs. car in its current state (all other aero and no front dam / belly pan) by lowering stagnation point and pushing majority of encountered air smoothly over top/sides of car to take full advantage of kammback, etc.
•Improve safety in a frontal collision by adding crush space and materials which provide significant support and resistance to crushing, but will fold up easily with substantial impact.
•Improve warm-up times in the winter by completely sealing off/controlling the radiator inlets.
•Improve ground clearance vs. original air dam
(notice my opinions about the shape of the air dam / nose of the car have changed.... more reading ;)
Pictures of progress thus far:
Framework and crumple zone complete:
Original plan was to have some of my spare lexan polycarbonate follow the curve of the following photo. Turns out this angle is way too far past the critical angle for air/polycarbonate. Translation: The majority of light from the headlight was reflected down to the ground rather than passing through.
You can also see my air inlets in this photo:
Had to solve the problem of the lexan angle; sacrificed some aero for it but still a big improvement over stock, I think. It's hard to see the lexan in this photo, but it comes down at about a 65 degree angle below the horizontal and meets a nearly horizontal piece of coroplast.
And here she sits... have to finish the other side and slap on some under-panels just going back as far as the engine/transmission to smooth things out and encourage the possibility of airflow through the radiator when it is needed. License plate will cover 2 of the 4 air inlets during the wintertime, and be moved in the summer. Planning an adjustable door for the other two.
Lifetime Fuel Economy: 39.49 mpg
View my fuel log here: http://ecomodder.com/forum/em-fuel-log.php?vehicleid=717