Downshifting with high throttle - an essential skill when driving a manual car.

To shift gears without the car jerking, drivers use a technique of pressing the clutch twice while simultaneously revving the engine to synchronize the speed.

Revving the engine or double-clutching the clutch was a common technique before manual transmissions became prevalent, and when synchronizers were not yet available. The principle for smooth gear changes is that the engine speed must match the wheel speed. If the speeds are mismatched, the gears on the two transmission shafts will be damaged or may even fail to engage properly.

The issue of synchronized acceleration is easily resolved when the vehicle is accelerating, as both the engine and the vehicle are increasing in speed. Conversely, when downshifting, the vehicle may be speeding along, but the engine speed decreases because the driver is no longer pressing the accelerator. Therefore, to synchronize the speed, drivers often press the accelerator very quickly (revving the engine) to make it easier to shift gears.

1. When should you use the double clutch?

In older manual transmission cars without a synchronizer, double-depressing the clutch is the natural thing to do. However, in newer cars, this technique can also be applied for smoother gear changes, preventing the car from revving or jerking, especially when downshifting, such as skipping 3rd gear from 4th to 2nd. Furthermore, this method helps extend the lifespan of the synchronizer; for example, when downshifting from 3rd to 2nd, the 2nd gear synchronizer experiences a delay, making a quick rev of the engine more beneficial.

2. Practice:

Find a secluded place to practice this move until you master it. Although this move poses little risk of causing accidents to others, practicing it in an area with minimal traffic is still the best option.

3. Start with a low number:

Accelerate to third gear, starting with lower gears to get a clear feel for the difference. Then depress the clutch as usual.

4. Regarding N:

After depressing the clutch, shift to neutral (N) and then release the clutch. At this point, the car is rolling in neutral, at a suitable speed of around 40 km/h.

5. Accelerating:

When the car is in neutral (N), quickly press the accelerator pedal with your right foot to increase the engine RPM, ensuring the engine speed matches the transmission speed.

6. Depress the clutch again:

After revving the engine, continue by pressing the clutch pedal a second time; this is why this technique is called double clutch.

7. Regarding the lower numbers:

8. Release the clutch pedal:

Release the clutch pedal to complete the downshifting process, but release it faster than usual.

According to VNE