O---K GUYS.....Y'all lost me at "IRREGARDLESS"!
I'm just a layman...not a member of the "FORD-ORDAINED CLERGY", and I don't know what all those lines mean...I just wanted a simple explanation...and I got it 6 posts ago!!!
Thanks, but jeez!!!...give me a break already!...my head hurts!

 

The longer stroke and larger bore is what limits the rpm's. Higher revving engines usually have shorter strokes and smaller pistons. Compare a piston and rod from our engine to gas engine and you'll be able to see how much more weight there is flying around in there.

 

A tall skinny guy and a short stocky guy are riding bikes up a hill, at exactly the same speed. Both of them weigh 200 lbs, and they are on identical bikes. Because they are moving the same load up the same hill at the same speed, they are generating the exact same horsepower.

However, the short stocky guy has stronger legs, so he is using a (numerically) higher gear, and his pedals are turning slower. The skinny guy has to use a lower gear, and spin his pedals faster to maintain the same speed up the hill.

They are both still generating the same power, whether you measure it at the wheels or at the crank. But the short stocky guy is generating much more torque, measured at the crank. (If you measured the torque at the rear wheel, it would be the same for both bikes.)

As you have probably already figured out, in this analogy the short stocky guy represents the diesel, the tall skinny guy represents the gas motor. Generally speaking, diesel motors are more pleasant and economical to tow with because they make their peak horsepower at a lower RPM than gas motors.

This does not neccessarily mean that diesels are more capable. Higher engine torque numbers do not necessarily mean that you can move a heavier load. The horsepower number tells the true tale of capability, provided that you have the proper gearing to utilize that power.

 

Not trying to beat the topic to death, but questions about torque vs. horsepower come up a lot here. It's hard to get your head around it. I'll just offer one more example. I don't recall where I read about it originally, but it was an article discussing how much power a mill's waterwheel made. An example I found is about a waterwheel that's 16' 4" in diameter and weighs 3500 pounds. It creates almost 6400 foot-pounds of torque (10+ times the PSD), but at 8 rpm, it only creates 9-14 horsepower. OK I'm done.

 

Man, I forgot how nice and flat the 7.3L curves were. Thats one thing I don't like about my 6.0L is how peaky it is, almost like a 2-stroke motorcycle.

 

OK, HP vs. Torque, an easy explanation.

2 guys work for you, Bob and Mike. They load 20lb sacks of grain into rail cars. Bob can lift 60 lbs, Mike can lift 20 lbs. Bob has more torque than Mike.

Bob loads 60 lbs a minute into the rail cars. Mike loads 80 lbs a minute into the rail cars. Mike has more horsepower than Bob.

Regardless of torque values, horsepower is a better measurement of towing capability. Torque mearsures raw pulling power, but horsepower measures that same power over time, or in other words a measurement of WORK.

As an example, remember back in the 60's and early 70's? You'd see 180 HP semi trucks pulling 80,000 pound GVW loads up and down the interstate....but they wouldn't go up hills very well. It was common in the mountain west to see those trucks creeping up the shoulder of a mountain pass a 5 MPH. A classic example of high torque but low horsepower.

 

True, but if you took a typical gasoline engine that makes a peak 180 HP, at probably 5000 rpm, it wouldn't climb the hill any faster, but it would puke it's crankshaft before it reached the top of the second hill.

I guess what hasn't been said is that there needs to be good balance of torque at low rpms and the ability to reach decent rpms with that torque (hp) to tow well.

 

Tens of thousands of horrible misspellings and grammar errors on this board and you pick this one to critique?

It's not proper form but it's a real word.

 

Don't go away! We're not done helping YOU!!!!!

 

Yeah, we know bluestuff is done with us. We're just arguing about manstuff now. You know, horsepower and torque.

 

Unfortunatly irregardless is a word. The definition even starts out with the word "probably". "Probably a combination of irrespective and regardless". It is of course a double negative so it should not exist. But hey it's English so what do you expect.

 

Here's another example using the same concept:
15 editted load a rail car with 20 lb sacks of grain in 4 hours. That's torque.

But, as expected, they load it wrong.

Their boss shows up and within a split second, notices the error, and in the next split second, fires them all without pay. That's power.

 

That particular word is a pet peeve. It's listed in the dictionary, but only to explain it's theoretical origin and explain that it's improper.



Sorry!!

 

Nice explanation, BUT torque, by definition, is a measure of force in a rotational direction not in a lifting direction.

 

The word debate reminds me of a Calvin and Hobbes cartoon where Calvin is taking a test. The question starts out "Describe in your own words..." The light bulb goes off over his head and he starts writing gibberish, saying "I love a loophole...."





That's really just not necessary, is it?