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Horsepower sells engines and torque wins races was quoted to me once apon a time.

Is torque and horsepower an equal equation, or can you have a greater horsepower figure to a given torque standard?

Or a greater torque reading to a given horsepower figure?

Cheers...
 

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Torque is the twisting power at a given instant...there is no time relevance to torque (that's why its measured in ft-lbs and not ft-lbs/sec or ft-lbs/min, etc)...it is just is an amount of energy available at a given instant.

HP is the amount of work done over time. HP is moving your car a specific distance within a specific amount of time.
 

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MMMM i love TORQUE..
Look at all the videos of the diesel pickups running under 13's in the 1/4 mile..
Ive noticed its not uncommon to have torque double the HP numbers..
but then again this is diesels not gassers
 

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Big torque without the ability of quick reving do not win anything ;)
+1......Think of a tractor or big rig.They can move mountains but aren't exactly quick...Big torque is much more forgiving if you are off a little with rear or trans gearing and that is why it is loved so much on a street car..
 

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torque gets you moving , hp determines how quick it reves is how it was explained to me. its a time thing. my f350 diesel produces about 570 ft.lbs. of torque max. it produces about 325 hp max. it has 4.10 rear and a 6 speed stick. i dont think theres anything on the road that i could outrun but it sure will pull 15,000+ pounds up steep mountain roads. the lighter the rotating weight the faster the engine will rev. excuse me while i kiss the sky !
 

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It isn't one or the other. Torque and HP are simple math and always directly related. As already said, torque is just a fixed force at any instant, and this is multiplied over time into the HP number. So, an engine with 200 ft/lb of torque* at 2000 rpms is making half the HP (76.2) of an engine with 200 ft/lb of torque at 4000 rpms (152.4). Simple math.

From this, you can see why tuners don't care about the other number, and only look at one (usually torque). An increase in one is a direct but factored increase in the other. So, why the ongoing arguments about which is better, especially if they are inseparable?

The argument stems not from which is better, but when each should occur. To a tuner, a high torque number at all rpms is a stronger engine. Duh. It's higher HP too. Simple math. But to a driver, having torque sooner to get things moving may be important, or having a peak later in the rpm band for a high HP blast down the straightaway may be the ticket to winning. Given that the typical engines we have make their best power in a 2000 to 3000 rpm band, the question is whether it makes it at lower rpms, or higher rpms.

To make it just a bit more confusing, engines can be designed with narrower power bands and higher peak HP, or wider power bands with lower peak but higher average HP In this case, the torque number is either played up or down, depending on whether average power is more important, or peak HP rating. Unless racing at a relatively fixed or narrow rpm range (offshore boats, circle track, NASCAR, air racing, etc.), the greater average power in your useful rpm range will usually get you to the finish line first. Because this shows on a dyno sheet as a higher and flatter torque curve, folks often say it's a 'torque engine'.

So, hopefully it makes some sense now that when hobbyists talk about which is better, they are actually talking whether a low-rpm or high-rpm oriented engine is better, or one with a broader or narrower power band. That, of course, depends on what you have and what you're trying to do. HTH

David

* For those that like to argue ft/lb vs lb/ft - note I said ft/lb instead of lb/ft. Ft/lb is just a force (scalar), and lb/ft is force with direction (vector). While a direction is necessary in power measurement and lb/ft would be appropriate, mechanical engineers established long ago that as TORQUE is specified (and therefore the direction), that only the scalar force is then specified - ft/lb. To say "200 lb/ft torque" is like saying "She has red hair hair".
 

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PSIG you are one smart cookie, very well stated. I donot think there is a majic number in hp and torque. I think every engine is different depending on how it is tuned kinda like retarting the cam or advancing. You can change the power band up or down making the car run on top where you would go through the trap or at the starting line. Moving that power also would change the torque to move along wit the hp, so as PSIG put it better in terms better they are married to each other , one works and moves along with the other. In my thinking wherever you wish both to work together best is related to how both reacts to the tires to hold best hook-up to get a faster time travel in such a distance. Whoever accuires that spot best when they find it working to their advantage they got their things working well and hard to beat.
 

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Guys that don' t make big horsepower numbers always want to talk about torque. Ever notice the pro stock guys don't ever talk about torque, only horsepower


JOE SHERMAN RACING ENGINES.
 

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Guys that don' t make big horsepower numbers always want to talk about torque. Ever notice the pro stock guys don't ever talk about torque, only horsepower


JOE SHERMAN RACING ENGINES.
You must be hanging around the wrong pro stock guys.
 
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