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kingsway · 03-10-2012, 05:34 PM

I've now done some slightly more valid test-runs. I found it very difficult, if the traffic is quiet, theirs too much wind or vice versa...etc etc !

Having discovered what a big difference in drag there is between a warm and a cold transmission, I pretty much convinced myself I was originally mistaken when I thought it was the airdam that seemed to be reducing drag.

I tried some coast-down tests today with the dam both on and off the car. I made sure both engine and transmission were properly warmed-up..

I'm not going to claim any great accuracy, but the airdam undoubtably has a quite noticeable effect!

The time to slow from 50 to 40 is, on average, about 3 to 5 seconds longer with the airdam in place.

The most suprising thing about this is the fact the dam is so flexible, it could only be folding back under the car to at least some extent under the influence of the oncoming airflow - so perhaps if the final version is more rigid the effect may be increased?

On my last tank-full I saw an average consumption of 43mpg (imp) - up from 36mpg previously. (P&G was the major reason for this)

When I get time, I'd like to try a full under-belly pan..

03-10-2012, 05:34 PM	#16 (permalink)
kingsway EcoModding Apprentice Join Date: Jan 2012 Location: Cambridge, UK Posts: 115 Thanks: 0 Thanked 14 Times in 9 Posts	I've now done some slightly more valid test-runs. I found it very difficult, if the traffic is quiet, theirs too much wind or vice versa...etc etc ! Having discovered what a big difference in drag there is between a warm and a cold transmission, I pretty much convinced myself I was originally mistaken when I thought it was the airdam that seemed to be reducing drag. I tried some coast-down tests today with the dam both on and off the car. I made sure both engine and transmission were properly warmed-up.. I'm not going to claim any great accuracy, but the airdam undoubtably has a quite noticeable effect! The time to slow from 50 to 40 is, on average, about 3 to 5 seconds longer with the airdam in place. The most suprising thing about this is the fact the dam is so flexible, it could only be folding back under the car to at least some extent under the influence of the oncoming airflow - so perhaps if the final version is more rigid the effect may be increased? On my last tank-full I saw an average consumption of 43mpg (imp) - up from 36mpg previously. (P&G was the major reason for this) When I get time, I'd like to try a full under-belly pan..