Here is a 5 speed gearbox:



Here is a 6 speed gearbox:



The working range of the engine is 2-3,000 rpm.

Why is it important to accelerate up to the speed limit promptly if safe to do so?

• It is to do with expectations, other road users are expecting you to get up to the speed limit and it makes driving more predictable for everyone if you do this.

Why do we change gear differently for performance and economy?

• For performance we would wait until we were around 3,000 rpm to get the maximum work from the engine.
• For economy we would generally change up at around 2,000 rpm to use fuel most efficiently, we would get slower acceleration doing this.

How would we use the gears for acceleration here?

• If we are in 4th gear and accelerating up to 70 mph we would stay in 4th gear right up until 60 mph where we would get maximum performance and then go into 5th gear for the last 10 mph increase and then for economy.
• If we are in 3rd gear and accelerating to 40 mph we would stay in 3rd gear right up to 40 mph where we would get maximum performance and then go into 5th gear as we would have reached the speed we want and now we go into the economy gear because no more acceleration is needed.
• If we had to accelerate more then we would go into 4th gear to get that further acceleration.
• If we are in 2nd gear and accelerating to 30 mph we would stay in 2nd gear right up to 30 mph where we would get maximum performance and then go into 4th gear as we would have reached the speed we want and now we go into the economy gear because no more acceleration is needed.
• If we had to accelerate more then we would go into 3rd gear to get that further acceleration.

How would we use the gears for economy here? (This is when there is traffic and we cannot get up to the speed of the road).

• We would go up the gears sequentially and at 2,000 rpm we would change to the higher gear.