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Old 02-10-2008, 04:31 PM
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bwilson4web bwilson4web is offline
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Real Name: Bob
Location: Huntsville, AL
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Default Re: Pulse and Glide Driving

Hi,

Quote:
Originally Posted by gpsman1 View Post
On 35 miles per hour or 40 miles per hour 4 lane roads, I do a lot of P&G in my FEH in the 25 to 42 miles per hour range. If there is light traffic behind me, I do 30-40 MPH.
So is this correct:
  • 25-42 PnG ~= 33 miles per hour average?
Quote:
Originally Posted by gpsman1 View Post
. . .
I usually net 10% better ( 44 MPG vs. 40 miles per hour ) compared to steady driving.
I think you are suggesting:
  • 33 miles per hour -> 40 MPG
  • 25-42 PnG ~= 44 MPG
Interesting, I'm see an 11% improvement with 25-43 PnG and your report is a 10% improvement. This is well within the margin of error.

I haven't done a sensitivity study to plot the sensitivity of PnG high-low speed values and the relative improvement over steady-state. However, it looks like something worth testing in the spring when 'standard days' return.

Quote:
Originally Posted by gpsman1 View Post
. . . I account some of it to thermal effects. The fewer number of minutes my ICE is on, the fewer minutes I am dumping heat into the radiator/environment... and by running the ICE water at 140'F with P&G vs. 188'F with constant on, there is slower heat loss to the environment by conduction/radiation... yes?
An interesting hypothesis and worth testing.

Bob Wilson

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