What is the effect of frequently increasing the speed on the engine? How to reduce the speed of the car at high speed?

In addition to the speed, the car's dashboard also displays the rpm, which is how many revolutions the engine makes per minute. On the tachometer, the highest rpm range is marked in red, which also means that it is best not to increase the rpm of the car frequently. So how do you reduce the rpm of a car at high speed?

What effect does frequently increasing the engine speed have on the engine?

The wear and tear of the engine can be generally divided into two working conditions. Under different conditions, the degree of engine wear is also different.

Cold engine status

Engine cold start

Experiments have shown that more than 90% of the wear and tear of the engine occurs at this moment. After being turned off for a long time, the oil in the upper part of the engine flows back to the oil pan under the action of gravity. If the engine is started at this time, the engine is in an oil-starved lubrication state due to lack of oil lubrication, which can actually be understood as dry grinding. This situation will continue until the oil pump pumps oil to the lubrication part.

Cold engine operation

After the engine is started, the oil temperature is low and it is suitable for slow and low-load operation. If you step on the accelerator hard at this time, abnormal wear may occur due to poor oil fluidity and inadequate lubrication. This is especially true for turbocharged engines. If you step on the accelerator hard in a cold engine, the heat cannot be dissipated in time and the turbocharger may be burned out.

Engine hot state

In fact, when the engine is hot, the oil lubrication system has been established and the oil temperature is in an ideal state. At this time, whether it is low speed or medium and high speed, there will not be much wear. In theory, the wear at this time can be ignored. Of course, if the engine is running at high speed near the red line for a long time, considering the high temperature shear force of the oil, it is still possible to cause greater wear. However, modern engines have already taken high speed operation into consideration during the design process, and generally the oil is cut off through ECU control.

How to reduce the speed of a car at high speed

Since the main transmission ratio of the gearbox and differential is already set by the factory, the general user cannot simply change the transmission ratio. However, when driving at high speed, reducing the engine speed at the same speed is beneficial to reducing fuel consumption, so reducing the speed ratio still makes sense.

However, under amateur conditions, there are only two ways: increasing the diameter of the drive wheel tire and changing the speed ratio of the highest gear of the gearbox. The former is more expensive and will increase the height from the ground, and will violate the tire specifications of the registration certificate, which may be punished.

The second method requires a special high-speed gear modification part for modification, which has a better effect. The disadvantage is that it needs to be installed by professional maintenance personnel, and the speed difference between the gears will increase, but you will not be stopped and punished by the police. It should be a better modification method.

Finally, modification is a systematic project. You cannot sacrifice other performance indicators for the sake of improving a certain indicator. If the improved performance is opposite or conflicting to the performance that needs to be sacrificed, and it will affect safety, modification is not recommended.

What does car engine speed mean?

The speed of a car engine refers to the engine speed, which is related to the working time per unit time or the effective power of the engine, that is, the effective power of the engine changes with the change of the engine speed. Therefore, when explaining the effective power of the engine, the corresponding speed of the engine must be pointed out at the same time.

The effective power and the corresponding speed specified on the engine product mark are called rated power and rated speed respectively. The working conditions of the engine at the rated power and speed are called rated conditions. The rated power is not the maximum power that the engine can produce, but the maximum usage limit of the effective power based on the use of the engine.

When the same type of engine is used for different purposes, its calibrated power value is also different. The effective torque also changes with the engine operating conditions. Therefore, the maximum torque and corresponding speed of the automobile engine can be used as indicators to evaluate the engine power.