View Poll Results: Horsepower or Torque what is more important?
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Poll: What do you think is more important Horsepower or Torque?
09-10-2009, 12:51 PM
#21
In trucks, especially if towing/hauling, torque is much more important. Why do you think Semi's have roughly 1200lb-ft but maybe only 350hp? Either way you need both, but bottom line is torque is required to get max hp.
09-10-2009, 01:11 PM
#22
Retired Aerospace
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Can't Have One Without the Other:
Horsepower is torque at some rpm. As it happens, horsepower is equal to torque at 5252rpm....do the numbers.
For rpm below 5252 torque is always greater than horsepower; for rpm above 5252, horsepower is always greater torque. It's just the way the numbers work out.
Of course we're dealing with lb./ft./seconds. Velocity at 5252 rpm is 550 feet per second.It's the reason that most heavy-duty diesels never have more hp than torque by the number. If a big diesel developing 1200 lb./ft. of torque could get that torque at 5252rpm, then the hp would be 1200 at that rpm.
That engine at 1200 lb./ft. of torque at 1533 rpm gets 350hp.
Last edited by Kattumaram; 09-10-2009 at 01:56 PM.
09-10-2009, 01:23 PM
#23
corey
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Horsepower is torque at some rpm. As it happens, horsepower is equal to torque at 5250rpm....do the numbers. For rpm below 5250 torque is always greater than horsepower; for rpm above 5250, horsepower is always greater torque. It's just the way the numbers work out. Of course we're dealing with ft./lb./seconds.It's the reason that most heavy-duty diesels never have more hp than torque by the number.
09-10-2009, 02:08 PM
#24
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De Veras. It'f Force-Feed or Bust:
Yep, it's hard to try to flow 1000 cfm through a valve port that maxes out at 300 or so cfm. You have obviously noted the falling torque value as rpm increases above a certain point. Eventually the line falls so fast that the horsepower line goes flat or begins to fall as well.....not a good idea to abuse a good engine like that. 
....and a complete waste of time and gas money.
....and a complete waste of time and gas money.
Last edited by Kattumaram; 09-10-2009 at 02:10 PM.
09-10-2009, 03:41 PM
#26
Sep 08' TOTM Winner
The way I know it is torque is how muc hwork you are doing, the HP is how fast you can do that work.
Look at it like this, a forumal 1 car has like 900+ hp, it does a little amount of work SUPER fast. Now look at a 80,000lb loaded tractor trailer, its got around 300hp and a *** load of torque, it does super amounts of work just slower.
The engine from that forumal car wouldnt move that tractor trailer. If you got a lite set up you want high HP to do (work son lol) work fast, and with a big tow rig you want alot of torque.
Thats how I understand it
Look at it like this, a forumal 1 car has like 900+ hp, it does a little amount of work SUPER fast. Now look at a 80,000lb loaded tractor trailer, its got around 300hp and a *** load of torque, it does super amounts of work just slower.
The engine from that forumal car wouldnt move that tractor trailer. If you got a lite set up you want high HP to do (work son lol) work fast, and with a big tow rig you want alot of torque.
Thats how I understand it
09-11-2009, 02:02 PM
#30