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Many people's first reaction in an emergency is to step on the brakes, and never thought of stepping on the clutch . It is because the impression that if the clutch is stepped on in an emergency , the anti-drag brake of the engine will disappear, which will increase the braking distance and affect safety. That is to say, with this idea, I tested it with a manual transmission car. The test item is whether there is a difference between the 100-0km/h clutch and non-clutch distance during emergency braking.
The popular opinion: When you brake suddenly, you should only step on the brake and not the clutch, because stepping on the clutch and then stepping on the brake at the same time will lose the traction of the engine , resulting in a longer braking distance and increasing safety risks.
Let's take a test. The test method is to brake from 100 km/h to a complete stop on a dry asphalt road. The gear used is 3rd gear (the reason is that the gear ratio of 3rd gear is close to 1.0, and the engine power is in this gear. The bit output is more direct).
Operation method 1: Depress the brake and clutch at the same time when starting to brake ;
Operation method 2: directly step on the brake to stop without stepping on the clutch . Of course, this method will stall the car.
This experiment uses the same manual transmission model with an ABS system. The two methods are tested 10 times each, and the best result is obtained. This comparison only looks at the results, to see how much difference the braking distance of the two operating modes can be.
The result may surprise most people. According to the data, the average distance of stepping on the clutch and brake at the same time is 7cm shorter than that of only stepping on the brake. Of course, this difference can be regarded as an effect, and there is basically no change. However, this result has proved that it is unrealistic to say that the reverse drag of the engine traction will reduce the braking distance in the case of sudden braking (one foot dead) .
From the experimental data, it is almost different from what I imagined. At 100-0km/h, the distance between the brake and the clutch is only a little different. In this case, there should be no debate about whether to step on the clutch or not for emergency braking , but in fact there is still a debate. After collecting relevant information, I learned why the clutch is stepped on during emergency braking and the reason for the vehicle Impact.
Potential effects of only stepping on the brake but not the clutch during emergency braking :
1. ABS is affected: Without stepping on the clutch , the engine 's anti-drag braking force may affect the normal operation of the ABS system, and in extreme cases may affect the control: such as the effect of emergency avoidance action, if it is slippery The road is even more dangerous.
2. It will stall: if you only step on the brake but not the clutch , the result must be stalled. Although the braking distance has not changed, there is still the possibility of a second accident after braking. If you stall when the second danger comes, think It takes a few more steps to escape, which is also a safety hazard.
3. Misoperation may occur: In an emergency, people are in a highly stressed state, especially for people with poor mechanical operation. In a panic, they may misoperate the pedal. If the brake and clutch are pressed at the same time , even Stepping on the accelerator by mistake will not affect the braking effect.
Since our test was conducted on a dry and flat road, the conclusion of this experiment is based on the results, that is to say, emergency braking on a flat and dry road can be operated according to the following conclusions.
Regarding the correct operation when the brake is suddenly braked, the clutch and brake are stepped on at the same time, please remember this method of operation. European countries have also given clear explanations and teachings on this issue. Even if the final effect of stepping on and not stepping on the clutch is almost the same, the potential harm must be considered.
Many things are not comprehensive enough to rely on theoretical analysis. The actual test results show that whether or not to step on the clutch at the same time will not basically affect the braking distance, but it may bring more potential dangers. Although the occurrence rate of emergency braking in life is very small, we must also understand what should be done in an emergency. The results of many things are determined by details. (Pictures, texts/ Auto House Wang Miao)