[gumby79]

V3
Most moddern cars use a Spat. A small 1-2 tire width mud flap looking thing 1-2" vertically angled slightly to the outside 1/3 tire. This softens the angle of impact, and redirects the air to go around the front tire with the smallest protruding wake(hence they stop short of the edge of the tire). This reduces the increases of frontal aera to the smallest number with the maximum effect. At some point the increases in frontal area (A)offset the improved side flow(Cd)
Coefficient of drag down, Aera up at equal percentages will net a zero change. In my cace I changed the A from a poor flow open suspension, to no flow solidthis increeced the frontal aera. As well as I went the same size as the bumper... yhis wound up 4"widerthan the tires.
Hear are some pictographs to further explain were I see my desine was for V1 , V2 and were I'm headed with V3
Some of verious situations I got into by reducing my aproch angle too much. (Moderators the system is fliping images agen)



And what the broken off part looked like.

V4
Hears one I scalped from a car lot gave me some ideas. A Toyota Tacoma pickup.

they (Toyotas aero team)solved some of my problems .
1 they taper up on tbe corners.
2 they moved air dam back under the bumper closer to the tire. Improving the approach angle ( less likley to experience a ground strike)
3 they kept it low full with to and used the center section as an intake duct for cooling. The air dam has a crease running horizontally were the loical stall poit is located(the point that the air has to go up and around or down and under).
4 not so good
Setting the air dam back and under like this will cause lift as the air( being pushed like a snow plow) builds high presure on the under side of this bumper. There is alredy low pressure at the front of the hood were the air separates at the transition to horizontal flow.