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Old 10-29-2011, 08:10 PM   #6 (permalink)
Patrick
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Join Date: Apr 2008
Location: Northern Florida, USA
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Hot Tamale - '10 Toyota Prius III
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Quote:
Originally Posted by Ladogaboy View Post
One thing that got me thinking is that, on a downhill freeway slope, my car will slow to less than 60 mph with no throttle. The way I look at it (possibly flawed thinking), that means that even on flat road, my car takes more energy than gravity to overcome its drag and rolling resistance alone at 60 mph. That seems to be a lot of energy, and I'm weighing my options for how to lessen it.
Yes, it is flawed thinking. The amount of energy available to overcome resistance (aero and rolling) is entirely dependent on the slope of the downgrade. IOW, the steeper the slope, the faster your car will coast down it. So the fact that it slows to less than 60 mph on your chosen slope really doesn't tell you anything. But it could be used to test your mods. After each mod, retest on the same slope. If you now coast faster than before, you know you've gained something from the mod.
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