Will I better gas mileage driving on flat versus hilly roads?

Answer 1

Assuming simialr distance / driving style etc, then ytes, without a doubt. You use more fuel going up the hill than you save cruising down the other side.

Answer 2

think of it like your body. what is the best for energy conservation while running? Hills or flat. you see, hills may give the illusion of easy downhills, but the up hills puts more strain on the body causing excess energy usage, and the down hills dont replace that spent energy. it doesnt add up. even if the flat was 4 times longer, you will spend more energy on the hilly road.

so the same is said of the car, and a flat road can mean that you can cruise at a constant and economical speed, while the hill uses excess fuel to compensate, and it uses more than twice the fuel, so is uneconomically viable for the purpose of economy.

if you can find a flatter road to travel, even if it is longer, you will save money. depends on the gradient of the hill though. but think of it like you would if you had to run that same road. common sense (sadly lacking in the first answerer) will prevail.

Answer 3

Better on flat, car doesn't have to use higher rpm to climb, whether you cruise down or not. It's like this math question-

#1 drives around the first half of a race track at an average of 90 mph. On the second half, he averaged 110 mph. #2 travels at a steady 100 mph around the track.

You may think that they tie, because the average of 90 and 110 is 100, but you can't average an average. My 7th grade math teacher told me this last week during class, and she has a phd in math.

Answer 4

You will always get better mileage on flat roads at a constant speed. Although one might think that the reduced engine load on the downhill portion will compensate for the increased engine load on the uphill drive, this is not the case. Friction, drag and varying the throttle, even downhill, will conspire to reduce economy.

Answer 5

on a flat road. Engine works harder to pull (or push) the weight of the car up a hill and even harder to maintain a constant speed. 55 mph (or 90 km/h) is the ideal fuel efficient speed to drive because at this speed your car is in final drive and your engine speed is relativley low compared to your travelling speed (meaning your burning less fuel travelling at 55 mp/h at 3000 rpm in final drive compared to 6000 rpm in 3rd gear travelling at 55 mp/h).

Remember, if going up a hill and you want to keep the same speed, your car has to raise the RPMs and to do that the car (or you) has to downshift to acheive that. Going back down a hill doesn't cancel that out because even with the gas pedal not being pressed the car is still burning gas to keep it running.

Hope this helps!

Answer 6

Yes. the motor must work harder to climb the hills. this decreases fuel mileage. if your always on perfectly flat surface you will have optimum mileage. (like you will ever fine a perfectly flat surface.)

Answer 7

hilly because you can put your foot off the gass and cruise down the downside of hills

Answer 8

Yes. UNLESS, all the hills are going DOWN.