Very weird question, Would be save more gas going up kill at 10mpg or going up hill at 25mpg (which

<div class='quotetop'>QUOTE(bluemoonseller @ Nov 9 2007, 03:17 PM) [snapback]537467[/snapback]</div>

Find the thread titled "uphill vs downhill". I think it is in this same forum, technical discussion. It has some very interesting opinions and ideas,

Icarus

Ps, I t is a simple math equation. The only thing that matters is units of fuel burned (net) over distance, not time. Do the math and you will answer your own question.

 

Hi All,

Lets See, we can figure this out in a non-algebraic manner.

3 minutes at 60 mph is 3 miles.

10 mpg is .1 gallons per mile (1/10), and

30 mpg is .033333 gallons per mile (1/30)

At 60 mph, you will use 3 times as much gas to climb the hill, or 3 times .1 = .3 gallon, versus 3 times .033333 = .1 gallon.

It would be neat to get a bunch of different speeds plotted for this. I imagine Robert J. Wilson has done this already though!

On the road, just tune the pedal for max mpg and your going to get the optimum.

The confusion you had might be related to pulse-and-glide comments. On the hill, there is no glide to offset the engine consumption. So, its just a matter of tuning the pedal for best mileage.

The hypermillers slowly decrease throttle from the flat terrain cruise speed, as they go up a hill, trying to the keep the engine in a max torque regime. Then let the car build speed by warp stealth on the down hill side.

 

<div class='quotetop'>QUOTE(bluemoonseller @ Nov 9 2007, 05:17 PM) [snapback]537467[/snapback]</div>

Since you have the same hill to climb each day, conduct a series of tests and find out:

1. set cruise control speed
2. reset trip meter and MFD at same point
3. read trip meter and MFD at same end point before leaving cruise control
4. calculate fuel burn
5. repeat for at least 3 samples at each speed or 5 and drop high/low

For good measure, bring the data back here and/or a plot like this one:

BTW, exceeding 65 mph ensures part of the hill climb data comes from the battery.

Bob Wilson

 

Actually I think you are over-thinking this. If the hill is x miles long, and you cover it at 10 mpg, it takes more gas than covering it at 30 mpg. Because the measure is MILES per gallon the travel time doesn't matter. No further analysis is required.

 

<div class='quotetop'>QUOTE(Bruce Boyle @ Nov 10 2007, 06:13 PM) [snapback]537839[/snapback]</div>

Or is the instantaneous mpg (whether steady or not) somehow different than the actual mileage for the hill?