v10 torque vrs diesel
Hello folks I have been looking for a used class A leaning towards a diesel as I plan on towing a Jeep and travel west coast, rockies Evidentially I am told that the newer V10 fords have very s...
Forum Discussion
Torque is a measure of the ability of an engine to do work. It's a component of, but not the same as, the horsepower of the engine, which is the rate at which work can be done. In an automotive engine, power and torque are related by a simple equation that considers torque, engine speed (in revolutions per minute), and a conversion factor of 5252
Torque x RPM / 5252
In this equation, torque is expressed in terms of ft-lbs, the engine speed is given in revolutions per minute, and 5252 is a conversion constant. An engine's horsepower, then, isn't constant, but rather varies with its speed.
Here’s the problem with horsepower... it is the potential or speed at which work can be done while torque is the ability to work....
While it is possible to take two 350 hp engines and make the same speed pulling the same load up an incline the one with the most torque at the lowest rpm is going to get there cheaper and usually faster because the other will require more gear reduction to produce the same forward force... Which will result in higher rpm’s needed, more fuel burned and more heat produced of which requiring more cooling which adds weight which requires more power (torque) or decrease in payload..
An example is my 6.7 liter diesel which produces 400 HP at 2800 rpm but 800 ft-lbs of torque at 1600 rpm... using the above equation one can see that the 6.7 produces 800 x 1600 / 5252 = 243.72 hp at 1600 rpm, far from the potential peak hp of 400 at 2800 rpm... Although in looking at the torque curve of the 6.7 it is apparent that the 800 ft-lbs is nearly constant through the range of 1600 to 2800 giving the 6.7 a very high work range.
The Ford V-10 gas engine produced 457 ft-lbs of torque at 3250 and 362 hp at 4750 using the above equation one can see that the V-10 produced 457 X 3250 / 5252 = 282.79 hp a gain of 39.07 HP but at the cost of more than twice the revolutions... to produce slightly more than ½ the torque of the 6.7 diesel.
While the design of the gas V-10 is aimed at higher RPM the life expectancy of an engine turning at well over twice it’s normal operating range is almost certainly going to be reduced by some factor if one expects it to produce the same work ability through increased rpm.. and gearing..
Torque x RPM / 5252
In this equation, torque is expressed in terms of ft-lbs, the engine speed is given in revolutions per minute, and 5252 is a conversion constant. An engine's horsepower, then, isn't constant, but rather varies with its speed.
Here’s the problem with horsepower... it is the potential or speed at which work can be done while torque is the ability to work....
While it is possible to take two 350 hp engines and make the same speed pulling the same load up an incline the one with the most torque at the lowest rpm is going to get there cheaper and usually faster because the other will require more gear reduction to produce the same forward force... Which will result in higher rpm’s needed, more fuel burned and more heat produced of which requiring more cooling which adds weight which requires more power (torque) or decrease in payload..
An example is my 6.7 liter diesel which produces 400 HP at 2800 rpm but 800 ft-lbs of torque at 1600 rpm... using the above equation one can see that the 6.7 produces 800 x 1600 / 5252 = 243.72 hp at 1600 rpm, far from the potential peak hp of 400 at 2800 rpm... Although in looking at the torque curve of the 6.7 it is apparent that the 800 ft-lbs is nearly constant through the range of 1600 to 2800 giving the 6.7 a very high work range.
The Ford V-10 gas engine produced 457 ft-lbs of torque at 3250 and 362 hp at 4750 using the above equation one can see that the V-10 produced 457 X 3250 / 5252 = 282.79 hp a gain of 39.07 HP but at the cost of more than twice the revolutions... to produce slightly more than ½ the torque of the 6.7 diesel.
While the design of the gas V-10 is aimed at higher RPM the life expectancy of an engine turning at well over twice it’s normal operating range is almost certainly going to be reduced by some factor if one expects it to produce the same work ability through increased rpm.. and gearing..
