What are the problems of high speed and high torque and low speed and high torque?

First of all, let's talk about torque, torque is a measure of how powerful a car is, which has a great impact on acceleration performance, after all, the greater the strength, the faster the speed.

Now let's talk about the maximum torque burst point, which is what you call the intervention time. Generally speaking, turbocharged engines have a higher maximum torque burst point and a wide peak torque platform, which can reach higher torque at lower revs and maintain it. The peak torque point of the naturally aspirated engine requires higher speed support, and the torque platform is also very narrow, but the naturally aspirated engine with variable valve timing and other technologies will have a double peak phenomenon, that is, although the maximum torque point is at a higher speed, there will still be a peak point of torque at lower speed, but this peak point is slightly lower than the peak point at high speed, and cannot be called maximum torque.

In general, in the city, it is true that a large torque is needed to burst at a lower speed, which is conducive to overtaking and speeding up, but when the traffic is jammed, the too low torque burst point is very depressing, and the turbo car will be pushed from time to time to scare you, which is the result of the turbine intervening at a lower speed. But when you usually drive, you rarely reach a speed of more than 4000, so the peak torque point of natural aspiration is for you to see, and it is rarely used in practice.

Personally, I still prefer the linear feeling of the naturally aspirated engine, and I don't like the abruptness of the turbo car, which generally can reach about 80% of the maximum torque at more than 2000 rpm, I think it is completely enough for daily use.

The wider the torque output speed, that is, the higher the maximum torque speed, the crazier the car will run after running, such as a supercar.

On the contrary, at very low speeds, large torque, or torque peaks can be obtained, and this kind of vehicle bearing capacity is relatively strong, such as trucks.

Usually seen at 5500 rpm peaking at 200nm, this type of tuning is generally focused on road driving, such as the Toyota GT86 and Audi R8.

If you see 2000 rpm or lower, you can reach 1000nm Generally buses.

The practice of driving at low gear and high speed increases the load on the engine, and the damage to the engine is great. There is also a common misconception in driving that is more damaging to the engine, that is, upshifting and overtaking. In fact, when the gear is higher, the engine torque is smaller, the throttle response is not sensitive, and the desired acceleration effect cannot be achieved.

The right thing to do is to actively downshift when overtaking and speeding up. For automatic transmission models, when the driver steps on the accelerator deeply, the trip computer will automatically make a judgment and downshift to provide enough torque to overtake. But only if the driver presses the throttle deep enough.

Engine torque.

Engine torque is the torque that the engine outputs from the crankshaft end. Under the condition of fixed power, it is inversely proportional to the engine speed, the faster the speed, the smaller the torque, and vice versa, it reflects the load capacity of the car within a certain range.

In some situations, the car is truly reflected, such as when starting or driving in the mountains, and the higher the torque, the better the car will react. Compared with the same type of engine car, the larger the torque output, the greater the carrying capacity, the better the acceleration performance, the stronger the climbing force, the fewer the number of gear shifts, and the relative reduction of wear and tear on the car. Especially when the car starts at zero speed, it shows the superiority of the high torque and the fast lifting speed.

What is the difference between a high-speed and low-torque car and a low-speed high-torque car, and what kind of road is suitable for each?

For family cars, the sooner the maximum torque rev comes, the better, and for performance cars, the focus is on how much power you can get at high rpm.

Is it better to have a lower or higher maximum torque speed", the question is actually very simple: it depends on the use. Let's take a closer look at this issue.

Why is the maximum torque speed high and low?

The fundamental reason lies in the size of the turbocharger, the supercharger is driven by exhaust gas, and the exhaust gas energy is small at low speed, and the large turbine can only push the small turbine if it cannot be pushed, so the engine that comes early in the maximum torque speed is basically a small supercharger, and the exhaust energy can be driven at low speed, such as many family cars now have the maximum torque at 1500 rpm. The engine with a large turbocharger must lift the speed to drive the turbo when the exhaust energy is large enough, so the maximum torque speed of these cars is basically after 2000 rpm.

What is the difference between high and low maximum torque speed?

The difference is mainly in the use, the most commonly used family car is the low speed range, for example, we usually drive at about 2000, or even lower, basically no one pulls the speed to 4-5 thousand rpm every day, so a small turbo for the family car can improve the power performance at low speed, which is good for fuel saving.

And those performance cars need horsepower, the more horsepower, the better, especially those cars that are racing on the track, basically pulling their necks to pull up the rpm in the race against time, even when slowing down in the corner, they must ignite the gasoline to enter the exhaust system and blow it up in order to keep the turbo spinning at high speed. These cars don't use low revs at all, so using a large turbo to improve the power performance at high revs is what stands out in the fierce competition.

Therefore, for family cars, the sooner the maximum torque speed comes, the better, and for performance cars, how much power can be obtained at high rpm is the key.

High speed and low torque are suitable for running at high speed, and the speed at this time is very fast The engine power is high, and the speed is high Low speed and high torque are suitable for running on city roads, and the speed is slow and the power is low, but the torque is full That is to say, it is very strong.

The car with low speed and high torque means that there is a relatively high torque output at a relatively low speed, and the car with high speed and low torque means that there is a relatively low torque output at a relatively high speed, and the car with high speed and low torque is suitable for driving on the road, and the speed is very fast at this time, the engine power is large, and the torque required will be a little smaller, and the car with low speed and high torque is suitable for driving on the road in the city, and the speed is slow, so the engine speed will be low, in this case, the car with low speed and high torque will be very strong, It's easy to overtake, take a start, and so on!

Generally speaking, when the speed of the car is very high, the speed is not very large, because there is no need to accelerate, so the demand for torque is not very large, and when the torque is the largest, for the whole car, the efficiency of the fuel conversion into useful work is the largest.

The answer comes out, if car A reaches the maximum torque at 4800 rpm, and car B reaches the maximum torque at 3000 rpm, and they are all the same power (for the same engine can be approximately equal to the displacement), at high speed, the high-speed speed limit is 120, and the actual speed is 130, at this time, the general vehicle speed is 3300 rpm, and it rarely reaches 5000 rpm.

On high speeds. First, the acceleration time of car B is short, and it is fuel-efficient; Two of the same 3300 rpm B have been running at maximum efficiency, able to maintain a speed of 130 too. Car A needs 4000 rpm to maintain a speed of 130, because the torque is relatively small, and the output useful work is relatively small, so the engine needs to consume more fuel to maintain the same speed. So car B is more fuel-efficient.

Of course, because of the high-speed speed limit, this is to keep the car degree is not very high, not at the maximum power when running, according to the engine power, speed, torque curve chart of the general low speed and high torque type torque will become smaller when the speed is very high, and the power determines the maximum speed of the vehicle, so not to the maximum speed comparison.

On city roads.

Needless to say, stop-and-go is faster, more fuel-efficient, and more flexible.

Old engine [low rpm] vs new engine [high revs] > economy**: Although I don't dare to admit myself as an old bird, but my understanding of the car is still more than the TX who generally only drives, not to mention that I have been driving for 9 years, and I have a few years of experience in responsible for the maintenance of the unit's vehicles, as for the cars I usually drive, work needs, everything But I have always had a question, I want to talk to the masters**== The old low-rpm engine [represented here by Jetta Sailo Parion] and the new high-rpm engine [temporarily representative] The phenomenon that everyone generally reflects is that the new high-speed engine is more fuel-efficient than the old low-speed engine, although this is not my personal experience, but everyone is golden, you don't see the new models are sold to 100 kilometers below how many liters of fuel consumption. New engine fuel efficient?

I have to admit that since the new engine is "new", there must be improvements, but these improvements are often reflected in how much power can be achieved under a certain displacement! We know that the key to really changing the speed [acceleration] of a car is torque! And the earlier the maximum torque appears, the sooner the vehicle will accelerate its speed, unless.... …You keep the revs above 3500 ......Does anyone drive like this in the city?

In today's increasingly urban traffic jams, new models are emphasizing their low-rpm torque ......On the contrary, in fact, the newer the engine, the later its maximum torque appears! The maximum torque of the engines in the older models mentioned above is 2500 sail:

2800 Palio: 2300 The maximum torque of the engine of the new model mentioned above is as follows: fit:

4800, SX4: 3500, TIDA: 4400 Obviously, the maximum torque speed of the ** model is higher than that of the old model, and it is much higher, so it is obvious.

The old engine reaches its maximum torque without using very high revs, which is more suitable for stop-and-go driving in the city. At the same time, the appearance of the maximum torque indicates that the engine efficiency conversion is the highest, so that the other engine will go the farther with the same oil when the maximum torque speed is exercised [without braking and decelerating].Therefore, in long-distance driving, it is most economical to drive close to the maximum torque speed....Does this just show that Volkswagen has been using 2-valve engines in the Chinese market for a long time, but it is actually for the good of the people? ......

The maximum torque speed unit is rpm, which indicates the maximum torque of the engine at this speed.

Torque is an important parameter of engine performance and refers to the average torque output from the crankshaft end when the engine is running.

The maximum torque generally occurs in the range of medium and low engine speeds, and as the speed increases, the torque decreases.

The maximum torque of the engine is related to the design of the engine's air intake, oil supply and ignition systems, and the maximum torque can be achieved when the performance of these systems is optimally matched at a certain speed. In addition, the power, torque and speed of the engine are correlated, and the specific relationship is as follows:

The power k torque of the rotational speed, where k is the conversion factor. When choosing an engine, you should also weigh how to use it wisely without wasting existing features. For example, it is necessary to turn on the air conditioner in Beijing in winter and summer, and it is necessary to take into account that the engine power should not be too small when choosing it; Just for commuting traffic on urban ring roads, there is no need to pick a high-horsepower engine.

Try to achieve economical and reasonable engine selection.

Power and torque are two of the highest indicators of a car.

1. The physical definition of power is the amount of work done by an object per unit of time. In the case of an internal combustion engine, we can understand it as the amount of energy produced by a fuel per unit of time. Therefore, power is only a physical quantity that describes the speed of workmanship, the higher the power, the more energy is produced per unit time, and often the top speed of the car is also higher.

2. The definition of torque on the engine refers to the torque output at the end of the crankshaft, and the magnitude of the torque determines the acceleration of the car. Therefore, torque is a physical quantity that measures the engine's ability to accelerate.

3. The relationship between power and torque: power = n torque speed, as can be seen from their conversion formula, n is a constant, then torque and speed are inversely proportional. This also explains why when the torque reaches its peak, it will drop sharply if it continues to pull up the rpm.

According to the formula power p = torque t angular velocity , p is unchanged, the smaller it is, the greater t is, the larger it is, the smaller t it is.

Mechanical components will produce a certain degree of torsional deformation under the action of torque, so torque is sometimes called torque. Torque is closely related to the working capacity, energy consumption, efficiency, operating life and safety performance of power machinery.

Torque, like power, is one of the main indices of a car engine, and it is reflected in the performance of the car, including acceleration, climbing ability, etc. In layman's terms, torque is an important criterion to measure the quality of a car's engine, and the size of a car's torque is directly proportional to the power of the engine.

The diameter of the gear (or pulley, sprocket, etc.) on the low-speed shaft is large, and the diameter of the gear on the high-speed shaft is small, and it is easy to analyze according to the lever principle. Note: The forces acting on the pitch circle, the outer circle of the pulley (belt), and the outer circle of the sprocket (chain) are equal, while the acting moments are different.