Originally Posted by
Daox
Actually, ripping around at high rpm and load isn't that horrible for fuel economy. Its when you start mashing the brakes that your fuel mileage drops like a brick. Using the brakes, idling, and real high speeds are the mileage killers. Acceleration doesn't have a ton to do with it, in fact, engines are more efficient at high load.
I would have to disagree a bit here. It's not "using the brakes" per se that hurts fuel economy, brakes obviously have no connection to the engine, rather their usage is the precursor to the likely fuel consumed (the MPG hit) as you accelerate back up to speed.
(A primary reason I "hate" traffic lights, especially the dumb ones that trigger on timers irrespective of traffic loads).
A constant RPM at the engine's sweet spot (pretty much what a CVT is designed to do) is a good bet for maximum efficiency (maximum respective to engine RPM, i.e., neglecting the higher frictional losses that CVTs have relative to a manual). Also while the efficiency of the engine may be 'better' at higher loads, less throttle (i.e., opening the throttle or nearer to WOT) means more fuel, more throttle means less fuel.
And most definitely I would say acceleration is the primary factor in fuel consumption. If we weren't accelerating we would use a minimum amount of fuel; it's Newton's second law: Force=Mass x Acceleration or looking at it another way - the Acceleration is defined by the force/mass. Velocity (speed) doesn't 'require' force (of course it does in our fricitional / real world, but really it's only because we are constantly fighting off the multitude of forces: drag, gravity, friction; the biggest effort an engine expends is the acceleration required (and defined) by the force/mass). This is also why the highway MPG usually exceeds the city MPG: highway - not a lot of acceleration, mostly a 'constant' velocity; city - lots of acceleration, rarely a 'constant' velocity.
That being said - you clearly know how to maximize your MPG (way better than me ), so "whatever" about all this theory mumbo-jumbo I have written above, you're doing it right.
ゼロ
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View my fuel log 2014 Mirage DE 1.2 manual: 33.4 mpg (US) ... 14.2 km/L ... 7.0 L/100 km ... 40.1 mpg (Imp)