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Old 09-27-2014, 02:26 PM   #15 (permalink)
The brake pedal is evil
Join Date: Jan 2013
Location: California__ Awsome: Yes
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Trolla - '94 Geo Prizm base
90 day: 35.82 mpg (US)

Ecomodded prizm - '94 geo Prizm Base
90 day: 37.88 mpg (US)

Dad's Corolla - '89 Toyota Corolla Base.
90 day: 29.51 mpg (US)

Denny's Detector - '08 Mercury Grand Marquis

Project E - '94 Geo Prizm Base
Team Toyota
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Originally Posted by mechman600 View Post
I think you know the answer to that!

Be aware that if you are trying to coast, DFCO should be used as a last resort. Why? It all comes down to engine speed. In order to DFCO, the revs have to be above 1500, which takes considerable more energy than idling at 700. Sure, no fuel is being used during DFCO, but it still requires energy, which is provided by the kinetic energy of your coasting vehicle, which was previously provided by gasoline (accelerating up to speed). You can feel the energy loss - the way the vehicle decelerates quicker when you are in DFCO vs neutral coasting.
My car will hold DFCO until idle for that speed so I usually downshift at 850 rpm. I can't get a good enough line of sight to be able to coast to a light EOC but I can in DFCO and have it turn green so I don't use brakes.
Getting sensor data off of a pre OBDII Toyota ECU via TDCL.
All of this is on E10: Project E is my current focus.

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