# Is torque more important than horsepower?

People talk about torque and horsepower all the time, and both numbers will be debated to death on car forums. But what exactly do they mean, and which one matters more?

## What is torque?

Torque is a measure of the twisting force your engine provides. It is usually measured at the crank (unless you’re Elon Musk, in which case you measure it at the wheel to inflate your numbers and confuse everyone who isn’t Engineering Explained). The units are usually either lb-ft (a force of 1lb positioned 1ft from the crank) or Nm (a force of 1N positioned 1m from the crank).

A car will usually give a peak torque figure. This is the most torque that an engine will provide at any point during its rev range. Usually it will say at what RPM this torque figure is reached, or sometimes it will show a range. At other RPMs, the torque produced will be lower than the advertised figure. Remember this fact.

## What is horsepower?

Horsepower is torque times RPM (times a constant - the number depends on what units you’re using). This is a measure of how much work your engine does in a certain amount of time. One horsepower is about 745 watts, or if you’d rather think of it in real terms, roughly the power needed to lift an average person 1 metre in 1 second. Once again, most manufacturers will quote a peak power figure which will only apply at a certain RPM.

## Does torque equal acceleration?

Consider the following two engines:

- Engine 1: 300hp @4000 RPM, 500lb-ft @1500 RPM
- Engine 2: 300hp @8000 RPM, 250lb-ft @3000 RPM

Which engine will make a car accelerate quicker?

The answer is that they are both the same if you allow different gear ratios. If you apply a 2:1 gear reduction to Engine 2, you halve all RPMs, double all torques and leave horsepower the same (since doubling something then halving something does nothing). Which gives you exactly the same stats as Engine 1.

The moral of the story is that RPM matters just as much as torque, since horsepower (and ultimately how much work the engine can do in a certain amount of time) is a function of both.

## What does torque actually mean?

Let’s consider another three engines:

- Engine 1: 300hp @6000 RPM, 290lb-ft @2500 RPM
- Engine 2: 300hp @6000 RPM, 390lb-ft @2500 RPM
- Engine 3: 300hp @ 6000 RPM, 290lb-ft @4500 RPM

Both have the same amount of power and the same peak RPM, so at 6000 RPM, they will all perform the same. But the torques are different!

Now let’s take a look at the power/torque graphs:

The torque curve doesn’t really matter all that much because it can be easily influenced by gearing. Horsepower is not changed by gearing, so focus on the power curve.

Engine 1 has a power curve that climbs roughly linearly because its torque curve is nearly flat. However, Engine 2 has more torque at lower RPMs, so its power curve is bulged upwards. Engine 3 has the same peak torque as Engine 2, but at a higher RPM. In the lower RPMs it has less torque so it delivers less power down there.

None of this really matters if you’re constantly near redline because they all produce the same power there. But most people don’t drive like that [citation needed], so they want power even when they put their foot down when cruising at 2000 RPM in order to overtake. Engine 2 has noticeably more power at that RPM so it will pull off the overtake quickest.

So in general, the larger the torque figure and the lower the quoted RPM, the broader the powerband and the more shove you’ll feel during “sensible” driving. Electric cars take this to the extreme since their peak torque figure is at 0 RPM.

## Where numbers fall down

The problem with these power and torque figures is that they only give two snapshots of an engine at two very specific RPMs. What goes on in between is anyone’s guess. Take a look at these two engines. Both of them have the same headline specs as Engine 2, but different characteristics:

Both these engines perform exactly the same at 6000 RPM and at 2500 RPM. But at other RPMs, Engine 1 is way better. At 4000 RPM, Engine 1 is producing 294hp to Engine 2’s 207hp. Of course most engines will have a broadly similar power curve shape, but you have to be careful because some technologies (hybrids, forced induction, VTEC etc) can distort the torque curve considerably.

The moral here? Look at the whole torque/power curve, not just the headline numbers.

## In short

- Horsepower is the best measure of both acceleration and top speed (assuming weight, grip, drag and everything else is the same).
- Torque doesn’t mean much without an RPM figure or range.
- More torque and lower peak-torque RPM usually means more low-end push which makes for a better daily-driver.
- However, headline numbers don’t tell the whole story.

Thanks for reading! Any feedback much appreciated!

*This content was originally posted by a Car Throttle user on our Community platform and was not commissioned or created by the CT editorial team.*

## Comments

I was getting ready to write up a little rant about this, but you have written it up so well that I can only compliment you.

I haven’t read this yet, but no lol. Torque and horsepower work together to propel a vehicle. It’s so annoying to see people say “yeah but horsepower is meaningless lel automakers dunno nuffin tork ftw”, when they really have no idea what they’re talking about. Or the classic “american engines suck because they don’t have the specific output of jdm xd”.

Those statements are idiotic because horsepower and torque are so closely related. It’s like saying comparing distance and speed.

Depends what you looking for if I where to build a off-road monster I would like torque while on the road probably just horsepower everyone has their personal preference :)

For off-road, wheel torque is probably most important, so you want lots of low gear ratios

5252

We need to get this to be a mod pic, because i can’t stand people having the most useless arguments over this 😅

When I look up dynos all I care about is the torque range, idc if my future car has 200 hp or 500 hpI just care about the torque range on higher rpms.

Lemme restate that, I mean I would like my horse in the 500 range but I just need good torque that’s all

I remember an anecdote in the matter.

Here in Spain, the Seat 1430 (Fiat license) came to the market in 1969, it was a good car, so it became popular pretty quickly.

There was another popular car at the time in Spain, the Seat 124 (Fiat licenced again); it was cheap and strong so it was also very popular.

But the 124 drivers notice that the 1430 was waay faster; when you look at the power figures that doesn’t make sense because, It only has 10 hp more!

The secret was in the power curve; in high revs the 1430 has 10 extra hp, but in lower ones reaches a 13 hp advantage.

Apart from a 25% superiority on torque of the 1430, that also helped.

Just a “practical example” that came to my mind. Nice explanation tho.

So, high torque at low RPM ia what pushes you in your seat, and horsepower at high RPM is what keeps you there?

Yep.

To quote Randy Pobst “Torque is what you feel, horsepower is how long you feel it”

Thanks for the summary!

I for one would like to propose a new way to measure the power and torque of a vehicle..

Over the full RPM range (eg 0-6000) what is the value of the total area under the curve for both HP and torque

You might have a car making 300 HP at 6000 RPM, but only 50 HP at 4000 RPM. Compare this to a car making 200 HP at 6000 RPM, but 170 HP at 4000 RPM.

Could prove for some interesting comparisons, and with equal gearing, even more interesting testing in real life.

Great job taking a complex concept and making it simple!

Yeah that is an interesting idea, but it’d get confusing with the units because the area under a torque curve would have the units for power (Nms-1), and the area under a power curve would be Nms-2 (horsepower per second anyone?!?).

Toque at the wheels is the best measure of acceleration. As you said, the power and torque curves won’t tell you how the car behaves unless you know the gearing.

I’m not sure when power comes into play though. The ability to keep providing torque? I know the power (and efficiency) affects energy use.

Nah, togue is a type of bean