Originally Posted by
QBridge
In manual cars for economy it's always good to keep the RPMs as low as possible by keeping the car in the highest gear possible with the car still moving and not stalling.
If I had a 6 speed manual and I was going 40Mph in 6th gear but I would have to keep foot all the way down on the gas pedal to keep car moving in 6th gear at 40Mph, woudn't that waste gas because I'm keeping the gas pedal down as far as it will go to keep the car moving?
Like on some old cars when the gas pedal is pushed that sends more gas to the engine. Since the engine cant go faster because the car is in 6th gear would the excess gas going in the engine be wasted?
Or say that I go from a dead stop in 3rd gear and to go in 3rd I have to push the gas pedal all the way down to make the car move. Wouldn't that waste gas?
two replies: When the car goes 40 in top you just have push the throttle far enough to make that happen. Another thing is when you have to accelerate you may have to shift down to allow quicker up-revving of the engine. Actually the most economic way of accelaration is brisk almost full throttle periods in each gear. Moving the throttle slowly in each gear is less efficient.
When you want to get going from a standstill in third gear, it is more a matter of fiddling with the clutch at low revs than giving full throttle with lots of slippage in the clutch as you suggest. Anyway this practice is to be avoided always....
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