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Old 10-22-2014, 11:58 PM   #26 (permalink)
niky
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Quote:
Originally Posted by brucey View Post
If I'm honest, I'm having a real hard time matching the EPA numbers in the new car, versus the old car where 50% over EPA was an obtainable number. I don't know if my hypermiling skills has eased up or if the EPA Cycle #s are a little optimistic to begin with.

Still satisfied with the mileage, but just not blown away I guess. I've also read that the mileage improves as the engine/car breaks in as well. Just seems odd still.
It's all about cycle-beating.

As greater and greater electronic control allow ever more specific engine tuning, manufacturers are gaming the test by making cars with very specific gear ratios, shift points and engine tuning, all designed to perform very well within the narrow performance window the EPA is test in.

Which means, drop your revs/speed or raise your revs/speed either way and you're out of that programmed "EPA Window" and into "regular driver" territory... where the engine is tuned more for power and reliability than ultra-lean cruising.

It's why more and more naturally aspirated cars are coming with a stupidly U-shaped torque curve. Gaming the EPA. The bottom of the U fits neatly into their planned acceleration profile.

Be nice if the EPA mandates economy over a wider range of situations. If you have to game the tests at ten different set speeds (say, from 30 mph out to 70 mph) and over three different acceleration rates... then the car is programmed to perform well for 90% of the people out there. That would be enough.
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