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Author Topic: Hills > Fuel economy Back to Topics
feeblegenius

Rookie Author
Connecticut

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Message Posted: Oct 3, 2012 6:45:34 PM

What are the best fuel economy tactics when traversing lots of hills?
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GrumpyCat
Champion Author Alabama

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Message Posted: Feb 13, 2013 12:08:19 AM

The thing about climbing hills is to avoid the highest power output from your engine which occurs near the top of the hill. High HP is less efficient per HP than that at lower outputs. So rather than race the engine up the hill let it come down the preceding hill a bit faster, hit the hill a bit faster with a bit more power than one would use on the flat. Pick a power output at the bottom and hold it all the way up. Let the vehicle slow, but not so much as to obstruct.

Hitting the hill faster stores energy as inertia.
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WTM
Champion Author Philadelphia

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Message Posted: Feb 12, 2013 9:53:16 PM

jrferrari wrote:"Accelerate before the hill, maintain going up the hill, slow as you crest the hill, and drift down the other side."

Well said, I do this everyday.
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eccerr0r
Champion Author Fort Collins

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Message Posted: Jan 26, 2013 2:40:22 PM

Yes, the idea is to conserve as much energy as possible. If you have to go up one hill and down the other side and there's no more up traveling after that one hill, it doesn't matter if you burn the brakes and go down slowly or if you zip down very fast. By the end of that hill, you have to lose all that potential energy else you'll crash.

However the ideal case when going up and down on several hills is to not use brakes when you can, and use the speed you acquire from going down a hill to go up the next. Of course this may end up making you reach unsafe speeds so you have to stop that...

Just going *up* hills is a different story, this is dependent on your car much like driving on flat roads. There is a sweet "speed" spot somewhere and it differs from car to car - where driving slower or faster would not be as fuel efficient...
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beachd8
Champion Author Orange County

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Message Posted: Jan 26, 2013 11:30:20 AM

Not much elevation change here. If I'm in hills, then I'm not usually in much traffic, so I'm using cruise control.
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jrferrari
All-Star Author Orlando

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Message Posted: Jan 26, 2013 11:01:03 AM

Accelerate before the hill, maintain going up the hill, slow as you crest the hill, and drift down the other side.
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TSgtCarverRetired
Champion Author Detroit

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Message Posted: Jan 19, 2013 11:26:39 PM

Put your cruise control on 65 - 68mph, and each time you go down hill it will not use any fuel since that is the way modern vehicles operate with the computers, and fuel injection. If you don't believe it try it.
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BlueberryFocus
All-Star Author Rochester

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Message Posted: Jan 19, 2013 11:18:42 PM

Like many have said already, speed up going downhill allowing gravity to help increase your speed and then allow your gained speed to slowly scrub off as you climb the next hill.
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traffic cop
Champion Author Boston

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Message Posted: Dec 30, 2012 8:53:02 PM

Houckster and several posters are right: Fast on the downhill, exploit that on the incline. But watch out for smokeys* when you're pushing the speedometer going down!

Also: avoid having to gain speed on the uphills, if possible.

*For the occasional ignorami on these boards, a "smokey" is truckers' parlance for a state trooper, so named because of his hat.
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sarasotasingle
Champion Author Sarasota

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Message Posted: Dec 30, 2012 12:24:29 PM

NO CRUISE CONTROL
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gvan
Champion Author Chicago

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Message Posted: Dec 30, 2012 12:13:58 PM

"The best way to get the best fuel efficiency is to pick up speed on the downhills runs when it's safe to do so and surrender the additional speed on the ensuing climb. This is what the truckers do."

Good advice but I'm not sure truckers have a choice. I think they do it to keep from significantly dropping speed on the uphill portion especially if they are running at 70-80,000 pounds.
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BUSSY
Champion Author Dallas

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Message Posted: Dec 29, 2012 11:48:27 AM

slow and steady
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moregas1966
Champion Author Columbus

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Message Posted: Dec 29, 2012 10:18:41 AM

drive slow
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WEPSMAN
Champion Author South Dakota

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Message Posted: Dec 29, 2012 9:41:14 AM

Take your time and do not try and speed up the hills. Let gravity help.
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JasTheAce
Champion Author Raleigh

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Message Posted: Dec 28, 2012 5:20:31 PM

don't tow a boat
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golfer7332
Sophomore Author Toronto

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Message Posted: Nov 18, 2012 8:27:23 PM

Blueberry says it best and don't use cruise control
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BlueberryFocus
All-Star Author Rochester

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Message Posted: Oct 22, 2012 11:31:21 AM

Ride the terrain - pick up speed going down hill, and scrub it off going uphill by holding the throttle constant.
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Banjoe
Champion Author Winnipeg

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Message Posted: Oct 22, 2012 11:08:12 AM

As usual, I'm with OceanArcher on the hill climbing approach.
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Maintroll
Champion Author Lexington

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Message Posted: Oct 22, 2012 9:50:45 AM

Don't use your cruise control and if pulling a trailer, don't have the vehicle in overdrive.
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OceanArcher
Champion Author Mississippi

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Message Posted: Oct 21, 2012 9:39:29 AM

I agree, constant throttle will be more frugal than constant speed. Only problem, the variation in your speed will upset the more aggressive drivers, so be sure to stay in the right hand lane and outa trouble ...
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cheapmonkee
Champion Author Portland

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Message Posted: Oct 20, 2012 1:45:14 PM

Yes, I think locking out OD climbing steep grades is beneficial many times and my MPG results would agree.
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Crapulent
Sophomore Author Mississippi

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Message Posted: Oct 20, 2012 1:32:45 PM

Houckster is exactly right. I have achieved all my best mileage readings that way, constant throttle rather than constant speed, which is just counterproductive.

I can't imagine why you'd want to kill overdrive. Maybe the poster meant kill cruise control?
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DanFMA
Champion Author Massachusetts

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Message Posted: Oct 20, 2012 9:36:15 AM

Take the transmission out of overdrive.
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Houckster
Champion Author Atlanta

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Message Posted: Oct 5, 2012 11:11:58 AM

The best way to get the best fuel efficiency is to pick up speed on the downhills runs when it's safe to do so and surrender the additional speed on the ensuing climb. This is what the truckers do.
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