Why horsepower doesn't matter!

[Comebackkid]

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For the last century, horsepower has been used to describe the power output of the internal combustion engine. The horsepower unit was created by James Watt in the 18th century. Its origin is based from how much power a horse could lift in foot pounds, 33,000 ft-lbs to be exact in one minute. The unit is derived from torque, which is the true measurement of the engine physical power production.

 

What is strange about the units of horsepower is that it has no physical meaning. Its an arbitrary unit that has no real signficance in describing the characterisitc of the engine. For those that are curious to calculate horsepower:

 

Horsepower=(rpm/5252)*torque

 

From this equation you can see that horsepower is nothing more than a contrived unit that is based purely from torque and rpm. You’ll notice the number 5252 in the equation, this represents the point at which every dyno graph must intersect horsepower and torque. Its a mathematical relationship, both strange and interesting since horsepower is a function of torque and rpm.

 

There has been much confusion and rumors across the internet about gaining more horsepower. In essence, gaining more horsepower is gaining torque. If you are after “peak” horsepower, you are interesting in carrying the torque curve as high in the rpm range without falling as possible. You can see from the equation that as the rpm’s increase, and the torque remains the same you get a higher horsepower number.

 

What phsycially is happening is that the engine is able to produce enough torque to overcome frictional forces through the air, tires, etc. As you are able to keep the torque from falling off on the top end, you are able to maintain a steady torque curve that will “pull” the car through the mph you are trying to reach. So people who are after “peak” horsepower really want to extend their torque curves as far towards redline as possible, without letting the torque fall off. Check out some dyno graphs and see what I mean. Horsepower doesnt describe the true nature of how the engine performs, its the torque curve.

 

From a tuners perspective, I dont tune off of the horsepower curves. The physical relevance towards the engine performance is arbitrary, since the torque is truely what is effected by the fuel, timing, breathing, etc of the engine. The horsepwer is merely a concocted unit of measure, showing no true characteristics of the engine power output. A good tuner will only make changes from the torque curves, see what increase/decrease the curves show from the changes. So next time you are thinking horsepower, think “what would I want my torque curve to be”?

 

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[Sully]

Sure it matters. Saying something along the lines of "I have a better torque curve than you" to someone isn't quite as fun and doesn't pack as much punch as saying "I have more horsepower than you".

[Draco-REX]

Horsepower is like Torque over Time... sorta. It gives a basic idea of where a car makes power. Otherwise, it would seem like the engine from a Semi would be the best drag engine you could drop into your car. Also, if we just look at Torque, a Forumla 1 engine would look like a slow piece of junk.

 

Horsepower has value, but it's far from the whole story.

[unfunnyryan]

Horsepower is like Torque over Time... sorta. It gives a basic idea of where a car makes power. Otherwise, it would seem like the engine from a Semi would be the best drag engine you could drop into your car. Also, if we just look at Torque, a Forumla 1 engine would look like a slow piece of junk.

 

Horsepower has value, but it's far from the whole story.

 

truck hits a max of 2800rpm

 

F1 engine hits 15000rpm

 

see where the formula comes to play?

[Total Sign]

This comes up every few years.

 

STFU.

[NOPR]

This a horrendously stupid post.

 

Yes, the term "horsepower" as a unit may be arbitrary, but the idea of power, or work done in a period of time, is anything but arbitrary. When considering engine output the most important number is power, period. You want as much power as possible, everywhere. Torque can be created with gearing.

[DavidBaustert]

There all arbitrary numbers, you know whats not arbitrary? Distance/time. Fuck the numbers game. Whoever gets to the the destination first is faster. This is kinda like the dyno argument or bhp vs whp. Different numbers on different dynos don't yield quicker/faster et's.

[Draco-REX]

truck hits a max of 2800rpm

 

F1 engine hits 15000rpm

 

see where the formula comes to play?

 

Exactly which is why just comparing Torque doesn't work.

[04SVT]

Definition of torque: You go to take a piss in the morning with a piss hard on and when pushing it down to hit the target, your heels come off the ground !!

[Evolved8]

This comes up every few years.

 

STFU.

 

:funny:

[AJ]

boats don't care about torque.

[Nickey4271647545519]

Build for TQ and HP will come with it.

[thorne]

Build for TQ and HP will come with it.

 

Tq follows the engine load

[Draco-REX]

Build for TQ and HP will come with it.

 

Only if you build for torque on the upper end.. I once again point to the diesels.

[iluvfastcarz]

I drive a Honda, what is this term torque that everyone is using?

[Tractor]

I drive a Honda, what is this term torque that everyone is using?

 

The number of pellets required to get the hamster through 6 revolutions.

[Comebackkid]

The number of pellets required to get the hamster through 6 revolutions.

 

I'll have about 500 pellets.

[unfunnyryan]

The number of pellets required to get the hamster through 6 revolutions.

 

Food pellets, or the actual thrust provided by the release of shit pellets?

[pontiacfreak142]

This a horrendously stupid post.

 

Yes, the term "horsepower" as a unit may be arbitrary, but the idea of power, or work done in a period of time, is anything but arbitrary. When considering engine output the most important number is power, period. You want as much power as possible, everywhere. Torque can be created with gearing.

 

gearing doesnt create torque, it just amplifies it. Torque deffinately plays a huge roll in how a car performs, but do i think its the end all, no. Like alot of guys have said, usually the higher up you can carry the tq curve the better off you will be. Take my car for example. I had always heard tq gets you moving, hp keeps you moving and the more power you have, the higher you will trap. Problem with that is, my car made about 226 whp at 5900 rpm and 237 tq at about 4600 rpm. My car is a beast off the line (1.82 60' at trails), but it wont trap for shit.

[brent1976]

I'm not trying to be a smart ass, but all you have in your sig is 500+whp civic, why no tq# if hp doesn't matter

[Benner]

The way I always heard it was "Horsepower is how fast you can hit the wall, but torque controls how far you take the wall with you"

[AJ]

The way I always heard it was "Horsepower is how fast you can hit the wall, but torque controls how far you take the wall with you"

 

that would be momentum not torque.

[Littleguy]

Somebody was spending too much time on Wikipedia again.

[Draco-REX]

Torque is your ET, Horsepower is your Trap.

[gillbot]

I sell horsepower wrenches.