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What about going up a incline? I gather the car with more torque? The same as having a car full? I'm trying to understand torque & HP. Difficult task ha!
You always need power. But if you have a car driving (it does not matter if they go up or down or on level surface), when you add torque to their wheels you add power, that is why you accelerate.
But lets say that you have two different cars (but with the same mass, to make it simpler) racing and accelerating at 50km/h. One has 200HP and the other one only 190HP. Lets also assume that they both achieve peak power at 5500RPM. Additionally lets say that manufacturer quotes that car with 200HP has higher max torque that the other one. So given that both vales are higher for 200HP car, you would assume that it would accelerate faster. Well in real life it
might not be so. The car with 190HP might have engine speed of 5500RPM at exactly 50km/h and is therefore transmitting 190HP (minus some losses) to the wheels. 200HP car might have an engine speed of 4000RPM at 50km/h. But at 4000RPM the engine is not producing 200HP, but only 150HP. So there are only 150HP (minus losses) available at the wheels. In such scenario, car with lower max power will accelerate faster.
If you want to get to the torque, you always have to think about torque on the wheels. Max torque on the engine output is completely irrelevant parameter. Much more important is the torque curve, max power and gearbox ratios. Only with this 3 parameters you are able to compare cars (you also have to consider mass, losses - those are higher if you have 4WD, and at higher speeds aerodynamics)
In the scenario above, wheels of both cars were turning with the same speed (if they were the same size). So if Power=Rotational speed x Torque, and rotational speed is the same, more power equals more torque. But that does not mean that car which accelerated faster (and therefore had more torque on the wheels) automatically had higher max torque quoted by the manufacturer. It just had better gearbox ratio for the above scenario. That is why more and more cars have higher numbers of gears. In that way you can drive at any given car speed closer to 5500RPM and therefore always be able to transmit close to max power to the wheels.