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The original article above concluded that
最大驅動力取決於引擎的馬力,和引擎的最大扭矩無關
This statement is theoritically true. I believe this is kind of misleading.
扭矩(torque) is still a very important factor to the performance of the car.
For example, we can put two engines below on the same car.
We will use a formula: hp = (torque * RPM) / 5250
engine#1 has flat torque
200 (lb-ft) from 1000rpm to 5000rpm
peak power is 200*5000/5250=190hp
engine#2 has a ^ shape torque,
100(lb-ft) at 1000rpm
linearly increase to 400(lb-ft) at 3000rpm
linearly decrease to 100(lb-ft) at 5000rpm
peak power is 400*3000/5250=228hp
Let make a test run and compare these two engine performance side by side
Let's assume that the vehicle has the such gear ratio at first gear
when vehicle runs at 10mph, the engine runs at 1000rpm
when vehicle runs at 30mph, the engine runs at 3000rpm
when vehicle runs at 50mph, the engine runs at 5000rpm
When the car starts, it is on first gear,
As you can see, at 10mph, engine#1 gives bigger drive force (驅動力) than engine#2 at the beginning
although engine#2 has bigger peak power.
So, Engine#1 (flat torque with less peak power) performs better
than Engine#2 (^ shape torque with more peak power).
Of course, you can say that at 10mph, engine#1 provides more horsepower (38HP)
than engine #2 (19HP).
But when you buy cars, you were only provided information of the PEAK horsepower.
If the car has unlimited number of gears so that you can always ajust the engine
run at the peak power at any speed, then you need only care about peak horsepower.
But the reality is, each car only has limited number of gear ratio. Therefore,
many times, especially at lower speed, you have to make engine run at non-peak
horsepower mode. At this time, the flat torque engine performs better because it
provides better horsepower and drive force earlier than ^ shape engine.
Overal, this statement is right
最大驅動力取決於引擎的馬力,和引擎的最大扭矩無關
But don't fool yourself by just looking at peak horsepower. The more scientific way is to look at the power curve shape (not the torque curve) against rpm.Usually the flat torque engine will boost power faster at low
rpm than ^ shape engine
The original article above concluded that
最大驅動力取決於引擎的馬力,和引擎的最大扭矩無關
This statement is theoritically true. I believe this is kind of misleading.
扭矩(torque) is still a very important factor to the performance of the car.
For example, we can put two engines below on the same car.
We will use a formula: hp = (torque * RPM) / 5250
engine#1 has flat torque
200 (lb-ft) from 1000rpm to 5000rpm
peak power is 200*5000/5250=190hp
engine#2 has a ^ shape torque,
100(lb-ft) at 1000rpm
linearly increase to 400(lb-ft) at 3000rpm
linearly decrease to 100(lb-ft) at 5000rpm
peak power is 400*3000/5250=228hp
Let make a test run and compare these two engine performance side by side
Let's assume that the vehicle has the such gear ratio at first gear
when vehicle runs at 10mph, the engine runs at 1000rpm
when vehicle runs at 30mph, the engine runs at 3000rpm
when vehicle runs at 50mph, the engine runs at 5000rpm
When the car starts, it is on first gear,
As you can see, at 10mph, engine#1 gives bigger drive force (驅動力) than engine#2 at the beginning
although engine#2 has bigger peak power.
So, Engine#1 (flat torque with less peak power) performs better
than Engine#2 (^ shape torque with more peak power).
Of course, you can say that at 10mph, engine#1 provides more horsepower (38HP)
than engine #2 (19HP).
But when you buy cars, you were only provided information of the PEAK horsepower.
If the car has unlimited number of gears so that you can always ajust the engine
run at the peak power at any speed, then you need only care about peak horsepower.
But the reality is, each car only has limited number of gear ratio. Therefore,
many times, especially at lower speed, you have to make engine run at non-peak
horsepower mode. At this time, the flat torque engine performs better because it
provides better horsepower and drive force earlier than ^ shape engine.
Overal, this statement is right
最大驅動力取決於引擎的馬力,和引擎的最大扭矩無關
But don't fool yourself by just looking at peak horsepower. The more scientific way is to look at the power curve shape (not the torque curve) against rpm.Usually the flat torque engine will boost power faster at low
rpm than ^ shape engine
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