Quote:
Originally Posted by Banana Jack
edit: by the way, this is essentially based on the idea that in order to get better gas mileage, rather than creep up to speed, you should use medium acceleration to get up to coasting gear faster.
|
When accelerating, you need horsepower.
An engine will produce that HP most efficiently al rather high loading (say around 80% engine load or so) and low rpm.
So you'd need to use a fair bit of throttle, but shift early - say 2500 rpm on a small(ish) displacement petrol engine.
But you don't really need to look at the current gear / rpm setting to decide when to shift ; you should look instead at what the engine will do when you get into the next gear.
You need to shift at the point where the engine no longer starts to lug once it gets into the low rpm in the higher gear.
The bigger the engine, the sooner you should be able to shift up.
Quote:
|
my theory is, why not drive a stick and just put it in coasting gear, even if you're only going 35, not 50?
|
The engine needs to be able to pull that off.
Some cars can do it , others simply can't.
If it can't, the ECU will throw on extra fuel just to keep the engine running, giving miserable fuel economy.