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Old 01-07-2010, 10:48 AM   #424 (permalink)
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Quote:
Originally Posted by Nerys View Post
I do not doubt the data. but part of good science is being able to reproduce data which is what I tried to do.

steady state or not 15% improvement "should have" shown up as more than a 1 or 2% difference in 400miles of driving where each leg is 54miles 1:20 minutes (basically that times 6)

if even 50% of my trip is relatively steady state (its much more than that but I don't have hard numbers) that means I should see at least a 7-8% difference.

then again It could also be my car. I might have something failing thats dragging me down (lately I have been maxing at 40-42mpg but its also been REALLY cold and really windy the last few weeks which might explain that.) so I have not tried to do it again till I have more consistent figures. because I damned well would slow down 10mph if it meant I could gain even 5% FE improvement :-)
That statement isn't true, because there are still times where you're accelerating as part of your measurement. If you're not using instant data, you're not getting a proper indication of the difference, and you can't assume that because you're doing the right thing for 50% of the time, that you'll actually see 50% of the result.

Also, you have too many other variables to accurately reproduce the test. Part of science is indeed the ability to reproduce the results, and that means using the same parameters, as well.

Darin's car is much more optimized, as is his driving style, than yours, so there is likely a bunch of unaccounted for variables messing with your data, including the likelihood of cross winds in multiple directions, changes in road surface, and speed variability over such a long distance.
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