Yeah I could probably find something by surfing the Net, but that could take me away from the Forum for more than 5 minutes. Not a pleasant thought.

Let me make more specific questions:

(1)-What is meant by the term "xxx ft-lbs of torque"? What is a 'ft-lb'?

(2)-Why does it matter? It seems to always come after horsepower when someone mentions the strength of a car's engine. But who cares how much torque it has?

(3)-Fill this in with anything else you think may show us how smart you are. Just to prove you know what you're talking about.

The link below contains a pretty good explanation. WAY too much to try to type though...
http://www.vettenet.org/torquehp.html

wow! ive bookmarked that page

Its a great primer on torque/HP
thanks

"Horsepower sells cars, Torque wins races"

quote Originally posted by Cheever3000: (1)-What is meant by the term "xxx ft-lbs of torque"? What is a 'ft-lb'? (2)-Why does it matter? It seems to always come after horsepower when someone mentions the strength of a car's engine. But who cares how much torque it has? (3)-Fill this in with anything else you think may show us how smart you are. Just to prove you know what you're talking about.

(1) The easiest way to mentally understand this is by thinking in terms of linear force being applied to a moment arm causing a twisting force about an axis. You multiply the force (lbs) by the length of the moment arm (ft) to get your torque (ft-lbs) or (in-lbs) etc. I can even give an example relating this to Fieros. The axle nut on a Fiero needs to be torqued to 160 ft-lbs. I didn't have a torque wrench that went to 160 ft-lbs. So how did I know that I was applying 160 ft-lbs? Well I weigh 160 lbs so I took my breaker bar that is 1 foot in length put it on the axle nut and stood on it applying all of my 160 lbs. You see torque can be measured as a linear force (my weight) applied to a moment arm (the breaker bar) about an axis (the axle). If I only had a 6 in breaker bar I would have had to weigh 320 lbs to create that same torque. So you can see that the torque is drastically effected by the moment arm.

(2) Torque is the ability to cause rotation in the case of a car the ability to rotate the drive wheels is what counts. Lets assume that we have wheels that are 1 foot in radius (this is our moment arm). If we have 160 ft-lbs of torque being applied to the rear wheels that is like someone pushing on the rear of the car with 160 lbs of force. So more torque means more force pushing the car forward. A force continually being applied to the back of your car would cause it to accelerate, thus torque is related to rate at which your car accelerates. The more torque the faster your car can accelerate.

(3) So Fieros only have about 160 ft-lbs of torque and we all know that by pushing a car with only 160 lbs would not cause much acceleration. So why is it that 160 ft-lbs can cause such a great acceleration out of our little cars? Remember that 6 inch breaker bar and me weighing 320 lbs? Well the transmissions in our car effectively reduce that moment arm way down so that we have much more force being applied from the same torque.

Edit so that you didn't see how stupid I really am.

[This message has been edited by Jefrysuko (edited 11-03-2001).]

Basically, horsepower makes you go fast and torque gets you there quickly.

I've always related HP more with top speed and Torque with getting off the line and out of corners...

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Michael ~ triadtuning@hotmail.com
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Photoshop rendering of planned exterior modifications.

When ya get over 140 hourses and 150 foot pounds of torque, Ya can't feel a 5 horse power increase. Ya CAN feel 5 foot lbs of torque increase.

There are lots of complicated ways to explain it but the one that made the most sense to me was,

Torque = Powerlifter

Horse power = a weakling runner

The Power lifter can lift big things(Car) but is slow.

The runner can run fast but can't pick up anything(Car).

So alone both are useless but together they work wonders.

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85 Fiero GT ~ auto 3.2 200hp 220tq ~ 75+ shot NOS ~ 0-60 4.9 13.5 1/4

An engine that produces a lot of torque is more fun on the street. It makes the car feel very light and powerful. A 70 Buick GS 455 generates 510 lb. ft. of torque at a very low RPM. Even though it is heavy by todays standards the car "feels" much lighter than my V6 Fiero on acceleration. Also getting slammed back in you seat is lots of fun! That is, if the tires ever hook up.

An S-2000 Honda is just the opposite. Nothing much happens below 5000 RPM. Then it's away we go! Unfortunately, you tend to attract the local constabulary with the screaming 8000 RPM engine note.

That is why the Caddy 4.9 swap will be so fun to drive. Real easy power that will make the Fiero feel much lighter. You won't have to dog the motor to get respectable acceleration.

Now the new Viper motor. 500 cid. 500 hp. and 500 lb. ft. of torque is a nice balance.
Don't you agree?

Rick 88

As I always say,
"Horsepower sells engines, Torque wins races."

torque * speed = horsepower.

They're the same (or rather, deriverative of each other, varaying on crank speeds), guys.

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Ben Cannon
88 Formula, T-top Metalic Red
88 Formula, Silver
87 Coupe, Metalic Red
"Every Man Dies, not every man really Lives"
-Mel Gibson, "Braveheart"

You can also think of torque as the measure of how fast you can develop peak horsepower.

Or for our Spanish speaking audience: Tu ...

(
"It is better to make torque at high rpm than at low rpm, because you can take advantage of *gearing*." :-)
Thanks for your time.

Bruce
)

good job bruce, i agree

Take a look here for an excellent explanation.

http://www.howstuffworks.com/question622.htm

quote Originally posted by Carrolles: Take a look here for an excellent explanation.

What you didn't like my explanation?

All of those together helped to complete the puzzle. I won't remember the details a year from now (okay, a week), but now I know when I read it, it's more important than just extra information. Now I need to keep certain numbers in mind for different engines, so I know what comparisons to make when I hear somebody's claims about theirs.

Jefry

Actually I didn't read it. I just happened to have found the article on Torque in the Howstuffworks web site and thought everyone might enjoy what the site has to offer.

heres how I say it....

Torque.... Joe benches 300 lbs in 5 secs..

horsepower... John benches 300 lbs in 2 secs..

both joe and john have 300 ft lbs of torque but john has more horsepower.