Air dam for higher top speed

[Chris67SS]

I'm trying to squeeze other 15 mph top end speed out of my 67 Impala SS. The steering starts feeling a little light before the car reaches the top speed its geared for. I wanted to keep the stock(ish) look of the front so I made this air dam for the car out of 0.125" aluminum. Its mounted about 4" behind the bottom of the bumper, following the contour, and about 4" off the ground and a 10 degree forward (at the bottom) angle, painted flat black. I haven't had the opportunity to try it out yet, any input on this project would be appreciated.

[Rick Dorion]

God, I like that! Can you provide any more specs? Or make me one! Please post back on the results.

[David Pozzi]

That looks good. you should be able to feel a difference with that. For testing, it would be great to take photos at freeway speeds or a little higher with and without the spoiler. A 3/4 front view or side view would be a good angle to judge front lift. If your front springs are stock rate, that allows more lift, and stiffer coils will lift less.

[Chris67SS]

After hours of research, I found that the vertical angle of this design air dam is wrong. It should be at a right angle to the ground for the most downforce. Anyway, there is a very noticeable difference at speed......Good idea about photos at freeway speed. When I pull the air dam off to adjust the angle, I'll do before and after video with the gopro. I'll post pic and specs when its dialed in

[Chris67SS]

I never did get a chance to do further testing as far as lift results on the air dam, traffic conditions weren't clear enough every time that I had time to test.
Anyway, The top speed increased to 153 mph at 5200 rpm and the steering feels solid so I would say it is an improvement. Also in side winds the car hardly moves at all now.
Nevada Open Road Challenge in two weeks! I'm there! Grand Touring division, 125 mph class

[Flash68]

Originally Posted by Chris67SS

I never did get a chance to do further testing as far as lift results on the air dam, traffic conditions weren't clear enough every time that I had time to test.
Anyway, The top speed increased to 153 mph at 5200 rpm and the steering feels solid so I would say it is an improvement. Also in side winds the car hardly moves at all now.
Nevada Open Road Challenge in two weeks! I'm there! Grand Touring division, 125 mph class

Nice work! And good luck and report back on the event.

[Vince@Meanstreets]

Originally Posted by Chris67SS

I never did get a chance to do further testing as far as lift results on the air dam, traffic conditions weren't clear enough every time that I had time to test.

watch that bro, I got babies on the roads.