Whenever the poweroutput of a engine comes up, there are two values that are mentioned. One is the power output which is expressed in Kilowatts or the old fashion way in horsepower. This is what most people recognise and have a idea of how much it is. Everybody knows that lots of horsepower is a good thing for the performance of the car. The other is torque, expressed in Newtonmeters in the metric system. But for most people, this is still a pretty vague term and they don't really know what it does and how much of it is a good thing for the the car.

There is a very complicated explanation for the term torque that explains everything using forces, opposing forces, gearratios etc, ect. But even I myself find it pretty hard to understand and it doesn't really make thing any clearer.

But I have come up with a example that everybody can relate to, to make thing a little clearer and easier to explain. I know it's not completly accurate, but it's good enough to explain a few things.

The example that we ll know: The bicycle.

I'm leaving gear ratio's and such out of the equasion in this story.

Imagine this: when you are riding your bicycle and you want to ga faster. What makes you and that bike go faster? Your ability to make the pedals go round faster. You might compare this to the horsepower of a car.

But when you get heavy headwinds or somebody jumps on for a ride of you might even pull a small trailer behind your bike, you will probably stand up on the pedals to be able to put more power down. You might compare this to the torque of the car which is very usefull for pulling loads or to get going.

So what is more important for a car engine.

Although power and torque will always be entwined with each other you can look at it like this: Torque will get you going from standstill and make you able to pull heavy loads. But if you want fast sprints and a high top speed, you are going to need horesepower.

Let's look at some examples: A Formula 1 car for instance. They have extremely high revving engines which put out a lot of horsepower, but haven't got much torque (The 2006 Toyota RVX-06 V8 F1 engine put out 740bhp at 19.000rpm, but only 274Nm's). The same goes for bike engines. The compact and high revving engines of a motorcycle engine can put out very high power outputs, but they really lack in the torque department. But they don't really need it. They will never be pulling a trailer or caravan and don't weigh much themselves.

But if we look at a truck engine, that will have to pull heavy loads at relativly low speeds, we'll see pretty high power output's. But at the same time, even higher torque figures! (The 2010 Paccar MX diesel engine put out a pretty modest 510bhp but at the same time it rates at whopping 2500Nm!)

The poweroutput of an engine is very dependent on the sort of engine and the engine design. A diesel engine can put out high torque numbers as can petrol high capacity engines.

A turbo or Supercharger can help to raise the poweroutput, but also the torque output of an engine.

I hope I was able to enlighten some of you on this subject.