Best FE uphill?

[Geebee]

What is the best way to climb in a small 4 cylinder, low revs high gear with say 1/3 throttle or let it rev at less throttle but in lower gears.
Thanks all

[Gregte]

Low revs in a higher gear will burn less fuel than higher RPM in a low gear with a fuel injected vehicle. A carburetor is another story. It can go either way with a carb, depending on how the carb jetting is set up.

[Doofus McFancypants]

If you can find the BSFC (Brake Specific Fuel Comsumption) plot for your engine - it will show you the "Sweet Spot" for efficiency - tends to be higher load @ lower RPM.

I have not been able to find one for my Nissan - checked several forums.

I try to max every downhill i can for the next uphill.
when taking on a hill from a stop - I try to accelorate compreable to that on a level road ( so there is a little more fuel used overall - but then i am "thinking" the same) and i try to anticipate the crest of the hill and back off to coast over.

Steve

[99metro]

I do about the same as Doofus. A hill is a hill and you are stuck climbing it. A little run up it whether from a flat road, or a previous downhill, will help get up it with little MPG loss. Back off the throttle as you go up, or back off near the end and "coast" up will be good. Now a big long hill - another story. Stay in your overdrive gear, low RPMs (don't get crazy though) and steady throttle all the way up; towards the end you want to gradually back off the throttle and get over the top enough to stay in your overdrive gear. If you have to down shift due to timing the top wrong, don't fret - it still works out ok with not a whole lot of MPG loss.

Some of my hills are rolling grasslands, so I can sometimes gain a tenth of an MPG from hill to hill if I do it right.

[IndyIan]

Originally Posted by Geebee

What is the best way to climb in a small 4 cylinder, low revs high gear with say 1/3 throttle or let it rev at less throttle but in lower gears.
Thanks all

On my scanguage with 30 to 40% throttle, in top gear, with the torque converter locked I get around 10L/100km at 90km/h climbing. If I let the car slow down to much where it lets the torque converter unlock at 75km/h I get around 13L/100km, downshifting a gear give me 16L/100km. So for me its always better to stay at a higher speed where I can keep the car locked in top gear. I don't have any hills where I can't climb this way.

I'd say a good rule to follow on hills with a manual transmission; Stay in the highest gear you can, using around 50% thottle without lugging the engine.
Ian

[jamesqf]

Originally Posted by IndyIan

Stay in the highest gear you can, using around 50% thottle without lugging the engine.

Works for me. Sometimes I can even get better mpg by going faster so I can stay in the higher gear. Of course this is going to depend on your car (mine's a Insight) and the particular hills you have to climb. AFAIK the only way to tell what a particular car will do, short of getting a BSFC plot and doing some calculations, is just to experiment. Try different ways, see what does best.

[Geebee]

Thanks for the feedback, At the moment I drive hills the way eveyone described, just thought I should check as the correct answer is not always the intuitive one.
We have LOTs of hills down here so it is a major part of my driving.
I am hoping to get a scangauge but I am trying to find out if my car supports it fisrt, it has the socket but I am not sure on the protocol.