Forester - Maximizing Fuel Mileage?

[Grolsch]

--

Do you actually have a roof rack, or do you mean the cross bars which
are mounted on the roof rails? Either way, yes. Get rid. You should
never leave the cross rails on when you are not using them. Weight
makes a difference as well. Don't caryy stuff around in your car that
you don't need.. Also, check your tyre pressures regularly and make
sure they are up to pressure. Running low tyre pressures will imact on
fuel consumption.

Biggest difference you can make is with driving style. It used to be
believed that gentle acceleration was the best way to go, but research
in recent years shows that it is much more efficient to accelerate
briskly up to your cruising speed. Anticipatory driving is most
important. Leave big gaps to other traffic, keep your concentration
levels high and think well ahead. That way, you can avoid losing
momentum.

What research shows that brisk acceleration is more efficient than gentle
acceleration, IMHO, it doesn't make sense vis a vis the Physics. Do you have
a source?

All of the above can make a difference of two, three or even four mpg,
which is significant on a long journey. To measure your consumption
accurately you will need to brim your tank to a point where you can
actually see the fuel every time and record the precise fuel quantity
and exact mileage. Don't rely on rough calculations or onboard
computers, which won't give you an accurate enough figure for your
purposes.

Alternately, you can fuel up to the auto stop on the nozzle and after a
dozen or so tanks the figures become pretty accurate. My experience tells me
that slowing down and calm driving style saves the most fuel. Just pretend
you have a full pint of beer on the hood, now drive without spilling any,
that's calm driving. Your heart and emotional health will thank you also,
not to mention your budget, insurance company, fellow motorists and your
car.

 

[Bruce Hoult]

Biggest difference you can make is with driving style. It used to be
believed that gentle acceleration was the best way to go, but research
in recent years shows that it is much more efficient to accelerate
briskly up to your cruising speed. Anticipatory driving is most
important. Leave big gaps to other traffic, keep your concentration
levels high and think well ahead. That way, you can avoid losing
momentum.

What research shows that brisk acceleration is more efficient than gentle
acceleration, IMHO, it doesn't make sense vis a vis the Physics. Do you have
a source?[/QUOTE]

Internal combustion engines produce the most power from the least fuel
at wide open throttle and lowish RPM. You therefore get the best fuel
economy at cruise from having a gear so tall that the engine can only
just maintain cruising speed with your foot flat. Unfortunately cars
these days have far too powerful engines for that (or alternatively the
engines aren't built to be able to run smoothly at full throttle and 200
RPM...).

But that best economy thing applies to acceleration just as much as to
cruise. Acceleration requires producing power. That power is most
efficiently generated by using a good bootfull of throttle at lowish
RPM. Press hard, and shift gears early.

 

[David Betts]

(Apparently nothng, because you appear to have inserted a sig.
separator at the top of your reply. I'll do my best without any
context.)

You ask for a source of the advice that it is better to accelerate
briskly to your constant cruising speed rather than dawdle. Sorry.,
but I can't quote one. Try googling. The research was widely
publicised, in the UK at least, several years ago. No it doesn't go
against the physics, just against the perceived wisdom. Modern engines
are highly efficient. They use less fuel in a brief burst of high revs
than a long slog at low revs. Also, you are far less likely to delay
and frustrate other motorists. And no, simply slowing down doesn't
necessarily save very much fuel, if any. It is the ability to maintain
a steady cruising speed on light throttle which makes the big
difference. Most people drive too close, don't look far enough ahead,
don't concentrate hard enough and don't anticipate well
enough....consequently they are always having to slow down, then speed
up again.

David Betts
(e-mail address removed)

 

[Carl 1 Lucky Texan]

(Apparently nothng, because you appear to have inserted a sig.
separator at the top of your reply. I'll do my best without any
context.)

You ask for a source of the advice that it is better to accelerate
briskly to your constant cruising speed rather than dawdle. Sorry.,
but I can't quote one. Try googling. The research was widely
publicised, in the UK at least, several years ago. No it doesn't go
against the physics, just against the perceived wisdom. Modern engines
are highly efficient. They use less fuel in a brief burst of high revs
than a long slog at low revs. Also, you are far less likely to delay
and frustrate other motorists. And no, simply slowing down doesn't
necessarily save very much fuel, if any. It is the ability to maintain
a steady cruising speed on light throttle which makes the big
difference. Most people drive too close, don't look far enough ahead,
don't concentrate hard enough and don't anticipate well
enough....consequently they are always having to slow down, then speed
up again.

David Betts
(e-mail address removed)

I recall that same advice once given by Consumer Reports - though it may
have been specific to a certain model car. I dunno

Carl