# Horsepower, and Torque..... whats the difference?

Discussion in 'The Garage' started by Silver84k5, Nov 25, 2003.

1. ### Silver84k51/2 ton status

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I was reading the 4wheeler mag, and they were trying to explain it to me. I cant see a difference. Can somone give me a few examples of differences between the two..... Or try to explain it better?
(this question may sound stupid but ive always wondered about it.)

2. ### zcarczar1/2 ton status

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Torque is the force that makes your vehicle move. Horsepower is a result of Torque and RPM.

3. ### 4X4HIGH1 ton statusPremium MemberGMOTM Winner

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It simply breaks down to this, Torque gets you going and HP keeps you going.

4. ### Topdown1/2 ton status

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I agree with the other two statements and will add this:

I always equate torque to pulling power and horsepower to passing power. Pulling power may only be the engine pulling the weight of your truck, but its still pulling none the less. I consider it acceleration from a dead stop.

so, 400hp = fast car 400tq = quick car (or burned tires)

Like I said, thats the way I have always seen them.

5. ### clubba681/2 ton status

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[ QUOTE ]
I agree with the other two statements and will add this:

I always equate torque to pulling power and horsepower to passing power. Pulling power may only be the engine pulling the weight of your truck, but its still pulling none the less. I consider it acceleration from a dead stop.

so, 400hp = fast car 400tq = quick car (or burned tires)

Like I said, thats the way I have always seen them.

[/ QUOTE ]
400hp &amp; 400tq = badass car! /forums/images/graemlins/thumb.gif
-Andrew /forums/images/graemlins/usaflag.gif

6. ### 99firehawk1/2 ton status

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Drive a modified rice burner that is called horse power

Drive a stock camaro that is called torque

7. ### Topdown1/2 ton status

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Andrew... you know that 410/425 small block sitting on the floor of my garage used to be in the /forums/images/graemlins/k5.gif right? /forums/images/graemlins/thumb.gif

since no-one is willing to pony up the green to buy it I think I might keep it and put it in an early chevelle or nova, I would love an old wagon to put it in... gotta love the old wagons. All the room, all the luxury, all the power! /forums/images/graemlins/pimp1.gif

-Ryan

8. ### Silver84k51/2 ton status

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HOw much you asking for, for that motor in your garage? a buddy told me about a deal from "Cylinder Head Exchange" (i think thats the name of the place) Where they have a 383 with 415 hp, and 425 foot pounds of torque, for 2 grand, with a 12k warranty.... Me and him both kinda thought that the deal sounded a little too good to be true....

9. ### Topdown1/2 ton status

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well, I have all the paperwork for almost all the parts and it totals out at 3000.00 with carb. (not including gaskets, bolts, balancer, distributor, flexplate, etc... or the cost of machining the block (bored .030 over), line-honing, magna-fluxing, etc... or assembly.)

So, I am hoping to get 3500.00 for it as that will cover all the parts and machining... I will have to eat the cost of assembly, Dyno, Tuning, etc...

I know its steep for a price, so I figure that no one will want to buy it (or no one can afford it) so I will keep it and use it somewhere...

10. ### Triaged1/2 ton status

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How about an equation (what else am I good for /forums/images/graemlins/confused.gif)

HP = Torque/5252

Have you ever noticed that ALL torque/hp curves cross just after 5000 rpm...this is why.

With the right gearing a motor with 350hp at 7500 rpm and 200 lb*ft will be jsut as fast accelerating as motor that has 350 hp at 5000 rpm and 350 lb*ft of torque. It has to do with how many fireing cycles per min are taking place.

11. ### Stroked72Blazer1/2 ton status

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He has it right HP is a calculation of torque. Hot rod Mag put it this way: Torque it how much work a motor can get done, HP is how long it takes to get said work done.

12. ### Blazer19701/2 ton status

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Torque is a measure of how much force the engine can apply to spin the crankshaft.

For any engine, this force is different depending on how many RPM the engine is turning.

Horsepower is a measure of how much work an engine can do.

If you have one engine that can produce 400 lb-ft of torque at 1000 rpm, and another engine that can produce 400 lb-ft of torque at 2000 rpm, you can do twice as much work with the second engine operating at 2000 rpm than you can with the first engine operating at 1000 rpm. The second engine will also be producing twice the horsepower at 2000 rpm than the first engine will be at 1000 rpm.

In order to characterize how much work you can really do with a given engine, you need to look at the torque curve, a graph that shows you how much torque the engine can produce across its entire operating range of rpm. The peak hp and torque numbers that are normally tossed around, and used in advertising DO NOT TELL THE WHOLE STORY.

Oh, and Triaged - you were close: HP = torque (lb-ft) X rpm / 5250

13. ### boz421/2 ton statusGMOTM Winner

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u are really close on your fomula. actually it is

HP = (torque x RPM) / 5252

14. ### heavy4x41/2 ton status

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Here's probably a more thorough (and easy to understand) explanation than you'll ever need.

15. ### Greg72"Might As Well..."Staff MemberSuper Moderator

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[ QUOTE ]

Oh, and Triaged - you were close: HP = torque (lb-ft) X rpm / 5250

[/ QUOTE ]

[buzzer]

Ooooooh sorry....the formula IS hp=(rpm x torque)/5252

[/buzzer]

It's always a good idea to doublecheck your formulas before telling Triaged he's wrong......Dan has a BIG brain! /forums/images/graemlins/thumb.gif

Personally, I like to think of torque as "real" and horsepower as "imaginary"..... /forums/images/graemlins/thinking.gif

....as soon as I see a service manual describing how much HP to apply to my bolts, I'll revise my thinking. /forums/images/graemlins/grin.gif

16. ### tRustyK5Big meanieStaff MemberSuper ModeratorGMOTM WinnerAuthor

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Torque is how much effort it takes to put your lug nuts on...hp is how long it takes you. /forums/images/graemlins/smile.gif

Rene

17. ### Thunder3/4 ton status

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Horsepower= How fast you hit the wall

Torque= How hard you hit the wall

18. ### TSGB1 ton status

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HP = Speed
Torque = Power to get to HP
No Torque and lots of HP = slow accel.

19. ### NetBlazerRegistered Member

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Greg has it right, Torque is where it's at, HP is a number speed parts maunfacturers like to throw around /forums/images/graemlins/smile.gif

I just had to get in on this post, because it's the subject of my .SIG

20. ### HarryH31 ton statusAuthor

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