# eli5 What is torque in regards to cars

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I’ve watched YouTube videos so o understand it’s to do with turning power but how isit linked to cars

In: Engineering

Torque is the twisting force required to turn your wheels and tires, which comes from power made by the engine .

As Jeremy Clarkson so eloquently put it:

Understeer is when your bonnet hits the wall

Oversteer is when your boot hits the wall

Horse power of how fast you hit the wall

**Torque is how far you take the wall with you**

In essence torque is twisting force and is determines in a vehicle A) the acceleration and B) the maximum load the car can push.

That’s why you have to shift to lower gears when going up a hill, because the lower gears give you more torque

Torque is a twisting force.

In a car, the motor turns a shaft with a good amount of torque. It then goes through a transmission to get that to a speed that matches the ground speed of the car instead of the speed of the engine. The transmission’s output shaft applies a torque to the wheels, which propel the car forward.

In cars, torque is measured at the engine’s output shaft.

the most direct way to explain torque is basically: “how much Weight can this engine push”. more directly it just means how much force does the engine transmit into the wheels to cause them to spin, more is good provided there is the mass to take it.

Take a wrench and use it to tighten a bolt. The pulling you do on the free end of the wrench is linear *force*, measured in newtons or pounds. The twisting (angular) force transmitted to the bolt is *torque*. If the wrench is a foot long and you pull with force equivalent to a free-hanging weight of 20 pounds, you are generating 20 ft-lbs of torque at the bolt head. This is the quantity measured by torque wrenches, where a fastener needs to be tightened to a certain precise degree, but not more.

The same principle applies to the drive axle(s) (or half-axles) in a car. With a bolt or nut you are tightening against frictional resistance until the bolt stops moving, but when driving a car you are spinning the wheels faster and faster, with as little resistance as possible. The more torque you apply to the axles, the quicker you can increase the speed of the wheels (ie, accelerate). Going 0-60 in 5 seconds instead of 10 requires more torque.

The torque number for a car is the max amount your engine is capable of generating under any circumstance. This peak amount varies with engine speed and gear ratio. High torque is what produces that satisfying pushback or “neck snapping” feel of acceleration. Electric vehicles typically have highest max torque at and near 0 rpm, so they excel at producing this feeling from a dead stop. Other cars with peak torque at higher rpms may feel sluggish off the line, but lively when you move to pass at speed on the freeway.

There are some bad answers in here and a descent one. Torque is the force on a shaft causing it to rotate. Internal combustion engines house cylinders with pistons inside them which are forced downward and upwards repeatedly applying torque to the crank shaft. That energy is transferred through the transmission, and rear end to the wheels through many complicated gears.

20 lbs. ft. of torque is 20 lbs of force applied to a shaft at 1 ft from the center of the shaft. This is why in terms of cars, you’ll hear 400 lb ft of torque at the crank, flywheel, tire etc. Depending on many..many aspects of engineering you can achieve different levels of torque and 400 lb ft of torque at the crank shaft will have a different amount of torque at the wheel.