Quote:
Originally Posted by toc
I can either pulse and glide between 55 & 70kph, or get it to 70 in 5th gear
|
With a petrol car, P&G should be more efficient.
Quote:
|
and not go hard on the pedal (maintain steady throttle position).
|
Accelerate at the BSFC - it'll be at a fairly high load
Quote:
|
An Idling car wastes fuel.
|
True, and that's where the major gain is with P&G : the engine gets shutdown on the glide.
Quote:
|
In fact, you are better off in gear going down hills, as your car will cut fuel, as it also will in gear and no throttle.
|
But you'd be (engine) braking.
That means this technique is less efficient, unless you actually need the braking action to keep your speed within legal or comfort limits.
Quote:
|
If in neutral, it will still use fuel, but with the engine unloaded (in neutral), the car will glide further - using fuel to idle as it glides.
|
My car consumes about 0.5 L/H.
Doing 100 kph, I'm seeing 0.5 L/100km or 470 mpg.
If I do 50 kph, I'm getting 1L/100km or 235mpg.
It'd be stupid to pass that up !
Under 15kph, I'm getting too close to my target fuel economy (4 L/100km - 58.8 mpg) for it to be worthwhile.
Coasting with the engine on is ultimately more efficient than rolling in (any) gear, and having the engine slow you down.
It's just a matter of properly matching your initial speed to the length of the glide.
I was an avid user of engine braking, getting good - not great - mileage out of any car I've driven.
Coasting engine-on improved my mileage considerably.