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Old 03-01-2014, 02:30 AM   #39 (permalink)
redpoint5
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Quote:
Originally Posted by serialk11r View Post
Right now engines are peaking at 37% or so...

I would think that there's perhaps only 10% more FE to gain from combustion cycle improvements left max (less for engines that are already direct injected and all) and if parasitic loads can be powered entirely by waste heat then we might be able to halve mechanical friction/load losses, for a grand total of 20%.
You bring up some good points. For clarity, are you saying that you believe we could gain 10-20% in MPG, or are you saying that we could improve current combustion efficiencies from 37% to between 47-57%?

A 20% improvement on a 40mpg car would be 48mpg. However, increasing combustion efficiency from 37% to 57% would bring a 40mpg car to 62mpg.

Either way, obtaining a 42mpg average in a decade is absurd.

People need to realize that rates of improvement, and in fact, rates of anything, are unsustainable. While possibilities may be limitless, the laws of physics and chemistry have very strict limits.
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