Playing with Lawn Edging

[CoyoteX]

http://cgi.ebay.com/Hammer3-Triple-T...QQcmdZViewItem

that is the horn I use. I used a fire extinguisher bottle for the air tank and a cheap compressor from harbor freight. It is a pretty simple setup but works very well.


I thought about why it would be lower on the sides and the only reason I can see is that it helps deflect air from the tires maybe. I personally don't care much about how my car looks so if this mod turns out useful I will probably extend it down to the pavement and let the pavement sand it down to whatever level works to keep it as low as possible to the road. I have about 3 inches of clearance on the front and I have not scraped anything yet so I should be able to get a good bit lower.

This is finals week at school so I probably won't get a chance to do a coast down test this week

[BeeUU]

Direct air from the front suspension; cooling air down the middle for the oil pan/exhaust?

My guess

[CoyoteX]

Well I managed to try and do a downhill coast test to see what I could figure out on this mod. With the front brake still dragging and the bad wheel bearing on the back I figured I might not get perfect numbers but I should still get an idea of what improvement it gives. I started with the edging on. Going up the hill I held the car full throttle in 4th gear trying to get speed up to the top of the hill. I managed to get to 60 by the time I was heading down. I went to neutral and let it coast. The car went past 80mph and was still accelerating at the bottom of the hill so I didn't hit a terminal velocity. I stopped and took the edging off and went back to try it again. Same setup this time, 60mph start at the top and it only went to 71mph and stayed there down the hill. I usually get about 75mph on that downhill run without the extra drag so that seems reasonable. I would have liked to do another run with the edging and accelerate down the hill to at least 80 before going to neutral to see what terminal velocity would be but I could already smell the front brake so I figured I might as well quit while I was ahead.

So for now I don't have good numbers other than to say it helps. If anyone has a flat front bumper extending it down is pretty easy and it definitely helps your aero out some. Maybe sometime soon I will be able to do a proper test but for now I need to do some work on that car and get it back in good shape.

[CO ZX2]

Thanx for the test results. 10 MPH difference in a coast test is significant. I have had the edging dam for quite a while but your results prodded me into adding another 3 inches to mine. I have hesitated to lower my car's front end because I live on a dirt road, can get pretty rough at times. I am now about 2 inches off the ground, both pieces are flexible and able to take punishment.

[kitcar]

I had better luck doing the opposite, having the center of the air dam lower, but then I have a truck. Might be the opposite for a car.