# what is the difference between torque and horsepower????

5

Asked by Feb 18, 2009 at 03:20 PM

Question type: Car Customization

25

torque is acceleration and horsepower is top speed and how much balls yer cars got lol

745

Torque is a measure of rotational force. Think about attaching a foot-long ruler to a screw and then hanging a 1lb mass on the end of the ruler. That is 1 ft-lb. In an engine torque is most closely related to displacement (and in particular the stroke of an engien or how far the piston move up and down). Forced induction engines with turbo or superchargers also develop more torque as a result of forcing more air into a smaller space (kind of like "faking" a bigger displacement engine). In terms of driving feel, torque is what shreds tires from a launch, gives you that kick in the pants feel on hard acceleration, and allows towing of heavy loads. But torque on its own does not necessarily mean fast. You need HP to be fast. Horsepower on the other hand is a measure of how much power is converted into mechanical work and transmitted through the crankshaft. THis is not to be confused with how much power is extracted from the fuel being burned. 1hp is roughly equal to 746 Watts of power. And in a passenger vehicle sized gasoline internal combustion engine roughly 33% of the fuels total energy is transmitted to the wheels. Another 33% is absorbed through the coolant as heat and dissipated through the radiator. And the remaining 33% is lost as heat through the exhaust. In other words a car has to burn gasoline that releases 300hp of power just to get 100hp out of the engine. The most efficient diesels can get closer to 50% but that is a stretch. Most gasoline cars are in the 20-35% range. I hope that answers your q!

8,745

Both of the above are correct. In terms of what it means in your car, torque is the amount of force you can put down on the ground as relate by the geometry of your drive train. The pound weight at the end of a ruler is a good analogy, but think of that same twisting force on the other end being used to try and spin that same ruler(minus the weight) against a wall... It pushes off the wall correct? In this analogy the ruler is your tire, while the wall is the road. Hence the more torque the more force to the ground. Newtonian mechanics, F=MA as your force goes up so will your acceleration (since your mass doesn't change) Horsepower is a little more complicated. It's actually a relationship between torque and engine speed. More specifically power = work/time... Work is just Force*distance... Because it's all rotational with cars hp= (Torque * Rotational Speed)*(a correction constant) the constant depends on the units you use. If you measure torque in ft*lbs and rotational speed in RPMs, the constant is (1/5252) IMO, horsepower is less useful a number than torque, at least on a street car...

35

horsepower is how fast you hit the wall torque is how far you push it.

25

lmfao that pretty much sums it up

1,305

its going to be hard to have horsepower without torque... considering horsepower is torque x rpm/ 5250... low torque=low hp

8,745

Generally that effects acceleration more significantly than top end.

8,745

??? I'm not sure what you mean??? I'm sure you're talking about NO2, but you should know that often NOS=New Old Stock... Anyway, Nitrous Oxide adds oxygen to the fuel charge allowing you to burn more fuel per cycle. (This is why a nitrous kit also includes a fuel sprayer and solenoid.) Contrary to popular belief you're not burning the NO2 you're burning regular gasoline, NO2 just supplies the oxygen. IE a NO2 tank won't explode in a giant blue flame when you shoot it. It'll spray compressed gas everywhere similar to what a diving tank would do. (Couple things to keep in mind, NO2 is a chemical additive and as such can/will react with a catalyst. This is bad if you have platinum plugs which will cause the NO2 to react much more readily and can/will cause severe pre-detonation... Also it ads oxygen, i.e. it simulates more air, as if air were magically forced into the system... It does for a short time what a turbo or supercharger does... Generally though it's a more extreme amount of oxygen) Anyway it's a 'power additive'... It increases the force created during a combustion cycle and in turn creates more torque. As I said before horsepower is just a relation of torque and engine speed, So if you have more torque at a given engine speed, you have more horsepower at that speed. Same applies for turbo and supercharger systems.

8,745

Your car has the same amount of horsepower and torque regardless of if it's putting it to the road or not mate, at least the way we measure when it comes to cars. Tires don't create force/power, they transmit it.

5

Id actually say tht bhp is how hard you hit the wall, and torque is how fast you get to the wall not push it, as to push it is your power to weight ratio!!

295

I like Chamal's explanation. Think about diesel engines and their long strokes. It translates into high torque, unlike petrol cars with shorter strokes and higher RPM, resulting in higher horsepower. Torque is the circular momentum, the raw pushing force that you feel. Think about bulldozers, slow but unstoppable due to the large force behind it. That's torque. And nitrous oxide decomposes to release oxygen into the pistons. Its kept in the NO2 form for safety reasons cuz carrying an oxygen tank connected to an engine is just suicidal. Oxgen, as we know is present at 21% in the atmosphere. Having NOS will increase that percentage inside the pistons temporarily for a better combustion rate. Of course, you might want forged steel pistons before trying that out.

torque is the ablity to do work and horsepower if im right is how far a horse can pull a sled until it quits. its been years sinse i heard that.

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