Torque vs Horsepower -- how do you use it?

[RafRaf]

Diesel Tsikoteers!

What's the main difference between torque and horsepower... and what is the right way of using it?

Thanks!
RafRaf

[luckytruck]

interesado din ako dito. puro hula lang kasi ang pagkaalam ko dito.

in my own guessing game, ang pagkaalam ko is high tourque means quicker acceleration/more pulling power. tama ba yun?

last na hula... i think that horsepower is the raw ability of the engine and torque is the horsepower mated to the gear ratios of the tranny and differential to produce pulling power or acceleration.

tama ba or sablay? hehehehehehe nanghuhula lang ako dito.

andy

[explorer]

articles taken from one of ford's intranet site:....

Ever since the horseless carriage replaced the horse and buggy as everyday transportation, people have used horsepower as a measure of motor muscle for machines.

Big horsepower numbers make big headlines and many customers look closely at the number of horses under the hood when they are out shopping for a new car or truck. They figure more horsepower equals better performance, but that's not always the case. The powertrain folks have a saying: people buy horsepower, but what they really drive is torque.

Truck customers value the pulling power of torque.

Torque also improves car performance.

"Torque turns the wheels," said Barb Samardzich, former chief enginner for automatic transmissions. "Torque is a measure of energy the engine is putting out that enables you to pull your load. If you have high horsepower, but you don't have the torque, you're going to have a hard time hauling that load."

Torque is what gets you rolling in the first place and horsepower keeps you moving along. The impressive 390 hp generated by the SVT Cobra is matched by 390 foot-pound of torque, and that 500 hp of adrenaline rush in the Ford GT comes with 500 foot-pound of torque. Keep in mind that these vehicles are among the top tier of high performance production cars, and they have the numbers to prove it. A more mainstream Ford Taurus has about 200 hp and 200 foot-pound of torque.

"Low end torque (below 3,000 rpm) is what snaps you back into your seat when you take off from a stoplight," said Gary Arvan, program manager, V-8 Diesel Engines. "Torque helps you accelerate off the line faster. It has a big impact on both car and truck performance."

More often than not, car customers look only at horsepower. It's a different story altogether for truck buyers. They are almost always more tuned in to torque. The wheels on a vehicle are basically twisting, and the twisting power known as torque is especially important to truck customers.


TorqShift with 6.0 Power Stroke Diesel engine.
"Truck customers know that without good low-end torque they are going to have trouble hauling big loads," said Samardzich. "With a lot of torque people would say 'that truck really has a lot of power.' If it doesn't have enough torque, people would say 'the engine feels like it's straining.'"

The 2004 F-150 will feature a new, more powerful, 5.4-liter three-valve V-8 engine that cranks out 300 hp and a huge 365 foot-pound of torque. Both numbers mark a big improvement for the top-selling Tough Truck.

"There's been a lot of discussion about horsepower wars in the media when they should be discussing torque," said Pete Dowding, manager, Ford Modular V-8 and V-10 Engine Programs. "People are towing bigger rigs and need the torque to pull those vehicles along. Our new 5.4 can go up against larger displacement engines and we're fully competitive against them in useable torque."


2003 Ford F-350 FX4
A diesel engine can give truck customers even more low-end torque and more efficient operation to make it easier to get the job done. Two out of three Ford F-Series Super Duty trucks are equipped with Power Stroke Diesel engines. The new 6.0-liter Power Stroke features a best-in-class 325 hp and a whopping 560 foot-pound of torque.

An engine that can crank out that kind of torque needs a durable and responsive transmission to deliver that twisting power to the wheels. The new Power Stroke features the all-new TorqShift five-speed automatic to meet the demanding needs of customers and the increased demands of high torque.

"More torque equals more power and more pickup and that means more performance," said Samardzich.

[luckytruck]

medyo malapt na rin pala ang hula ko

andy

[mcjayz]

In discussions about cars, people love to get worked up about horsepower.

"My car has 200HP," grunts one.

"I changed air filters and gained 5HP," grunts another.

But really, what does horsepower mean for performance? In truth, claims like the above tell you very little about how fast a car accelerates.

First off, figures like these are a measurement of horsepower at a specific RPM. We're talking about cars engines, though, which run over a wide range of speeds. When an auto manufacturer states their engine produces 240HP at 6000RPM, it means that ONLY at 6000RPM is it capable of 240HP. At speeds above and below that, the value drops.

Furthermore, horsepower is in a sense, unimportant. Horsepower doesn't move a car. It is really a measurement of how capable the engine is of maintaining the force that really is moving the car. I'm sorry about the vagueness, I'll try to clear things up as we go on.

What does move the car? What makes it get from 0-60mph? The same thing that basic physics teaches us is required to move anything: Force.
( my share so topic, u cn see d full dtails of this in this website. http://ubermensch.org/Cars/Technical/hp-tq )

[Walter]

Horsepower sells cars.
Torque wins races.

[RafRaf]

Akala ko kasi torque is limited to pulling power (like carrying loads and stuff) and horsepower is a factor in getting speed.

So in practical terms, when I check my manual/specs... if I want to get the most speed, I should operate my ride at its max torque spec (get into the specified rpm)?

[luckytruck]

as far as i recall, someone on this board said that in order to accelerate in the most efficient manner (not waste any engine force), shifting should be done at the rpm where there is the max torque. anything above that, you are just wasting energy. tama ba yon?

andy

[xox]

i still don't get it btw, is torque like acceleration which measures speed without the weight of the car or is it more like horsepower where you have to take into consideration the weight?

I mean a 0-100 7 sec. car is as fast as a 0-100 7 sec. truck, however a 200 horsepower car should be faster than a 200 horsepower truck keeping everything else other than weight similar. Which is torque more related to? Will a 500lb-ft car be as fast as a 500lb-ft truck?

[racerx]

ako analogy ko ganito:
torque parang diesel engine while horspower parang gas. puwede mong istart from standstill on 2nd gear ang diesel while sa gas, baka mamatayan ka ng makina unless you step on the gas more and slip the clutch.

another thing to confuse you is the characteristics of the L300 gas as compared to the 2.0l engine of the adventure. mas torquey (IMO) ang sa L300 gas pero may higher top speed ang adventure. hth