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Old 07-12-2014, 02:00 PM   #13 (permalink)
Ecky
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Join Date: Dec 2011
Location: New Zealand
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ND Miata - '15 Mazda MX-5 Special Package
90 day: 39.72 mpg (US)

Oxygen Blue - '00 Honda Insight
90 day: 58.53 mpg (US)
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Quote:
Originally Posted by Old Tele man View Post
It's ALL about how much HP is needed at the speed you're driving to overcome BOTH aerodynamic drag (which predominates above about 50 mph) and rolling drag (tires+mechanical+friction which predominates below about 50 mph). In either case, the HP requirement increases as the CUBE of velocity (V^3), so the faster you go that vastly MORE HP you're gonna need.
True, but in the case of my Del Sol, I have an undersquare motor spinning 2-3x as fast as necessary to generate the horsepower needed to cruise in top gear. I can throw it in 5th at 15mph and accelerate up hills. 5th is somewhere between 2nd and 3rd in my Insight.

With how it's geared, it definitely feels fast.

Spinning at 4000+rpm, there's a ton of wasted potential from friction and pumping losses and low cylinder pressure.
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