Quote:
Originally Posted by KamperBob
Phil, nice post. I know you prize accuracy especially with data so I thought you might want to correct something. Comparing Cd 0.3 to 0.1 is a three fold change but not 300% difference. It could be either 200% increase or 67% decrease depending on baseline (direction of comparison). It doesn't change your main point. A two fold change would still back it solidly.  |
Thanks Bob,I'm prone to self-delusion so lets see where my synapses shorted.
I ran calcs for a Miata-sized car of 17.7 square-ft Af,90.93 ft-sec,at Cd 0.30 and 0.10.
Road load @ 0.30 was 8.637 hp
Road load @ 0.10 was 2.879 hp
Delta-HP = 5.757 hp
8.637/2.879= 3 ( this is where I'm getting the 300% ( 2.879 X 3 = 8.637 )
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On the Cd part,
0.30/0.10 = 3 ( 300 % )
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Since Cd was the only variable it was looking like the exercise could be reduced to just comparing Cds,and on a percentage basis.Is this valid?