Neon airdam testing

[TOOSTUBBORN2FAIL]

Since this became such a heated topic on the neons forum, I decided to do some coast down tests between the stock airdam, and no airdam. The test was an A-B-B-A test, where the A tests were without airdam, and the B tests were with. For each test, I got two coast down times, one in each direction. Ambient temperature stayed at 64 degrees for the duration of the test, humidity at 39%. 3mph wind NW, test direction was East then West. Coast down speed was timed from 65mph to 50mph on an empty road. Tests were not done while cars were passing.

A 1- 22.3 sec 2- 20.6 sec

B 1- 21.1 sec 2- 19.9 sec

B 1- 21.4 sec 2- 20.1 sec

A 1- 22.7 sec 2- 21.0 sec

Average them together, and it shows a 5% increase in drag with the stock airdam on the car, vs without it.

This is the airdam in question. It is a stock piece. The issue is that without this piece, a stock neon would overheat. So the car needs a ducted radiator.

[AndrzejM]

Interesting numbers... It shows that air dam is not always helping. I've planned to attach one to my Berta, but now I know that I have to use cardboard model first and take it for a spin to do A-B-A tests.

[maczo]

Judging by the photo, the airdam is pushing the air into the engine compartment, not over the car (as opposed to the recommended location, extending from the bumper). Given that, the results shouldn't be surprising, right?

[TOOSTUBBORN2FAIL]

Originally Posted by maczo

Judging by the photo, the airdam is pushing the air into the engine compartment, not over the car (as opposed to the recommended location, extending from the bumper). Given that, the results shouldn't be surprising, right?

This was exactly my argument on the neon forum. Theres a guy there that built an engine undertray, and this guy that sells "airdams" like the one above, but that extend an inch lower, and extend several inches wider on both sides, is trying to convince people that its more aerodynamic. Hes also trying to say that a duct for the radiator wont work unless its inlet is inches from the ground.


Aside from that, after seeing a few new neon people on this forum, I figured it would be a good test to run.

[BamZipPow]

I guess the front end looks like this?

[TOOSTUBBORN2FAIL]

Yep, that's the "monster" airdam that the guy sells. Easily 3" wider on each side, and extends an inch lower.

My car currently has the lower airdam blocked so only the two inner most openings were open, and the fogs were covered. Unfortunately, the upper crossbar piece for the upper grill is removed, as I'm in the middle of working on a new bumper for the car that covers it completely. That will get finished as soon as the radiator duct is done. Problem is, epoxy resin doesn't do too well in wet weather.

[TOOSTUBBORN2FAIL]

Wow, said thread on the neon forum went down the toilet. Apparently, coast down tests are worthless, wind tunnels are the only way to measure drag, and the huge airdam might actually help mileage by slowing the car down to a lower speed. Oh, and dodge wouldn't add it stock if it wasn't the best way to do things.