Gas vs Diesel Hp vs Torque

[MossRoad]

And at -20F like it was this AM, I ain't going out to see which way my breath is blowing!!

jb

Sound like a good day to go ice fishing instead.

 

[Egon]

In those cases wet a finger and hold it up. You will know from where the wind blows and how hard. Just enough information to adjust for windage.

Egon

 

[Iowachild]

Here is a good article comparing a 22 HP Kohler Command gas engine with a Kubota 22 HP diesel.
Why Diesel Engines?

 

[cp1969]

I didn't read the whole thing but the paragraph that begins with

The definition of torque is : Force x Movement = Work.

is cause for concern. That is definitely not the definition of torque. Torque is force x moment arm = moment(or "torque") It is not a unit of work until it is multiplied by an angular displacement.

 

[KICK]

I hope winter is over for you all soon, very soon.

 

[cp1969]

None of the equations are seasonal.

 

[john_bud]

None of the equations are seasonal.

Obviously you've never attempted to start a gas or diesel engine at -20F! You can only compare the two if the diesel isn't in a semi-solid gel state! An engine that won't start has no hp to compare. Brrrrrrr

I have to go to the doctor now, I licked my finger and put it up in the 25 mhp wind and froze it solid. (Thanks, Egon! --- I'll get you for this...)



{just kidding ;-) )

jb

 

[gemini5362]

As said before HP is HP, no matter what type of engine it is produced with. Torque is Torque no matter what engine produces it. However, I think part of the confusion with this discussion rests on the people comparing the peak HP numbers. In the case above the 20HP lawn mower makes it's HP at high RPM. As the load on the machine increase (tall grass) the RPM is reduced and the eninge power output is also reduced substaintially(but torque goes up a bit). For the Kubota, the same applies but the load increase (tall grass) only slows the engine down a small amount because it's engine torque increases substaintially with a decrease in engine speed. Yes, the gas engine also increases torque but not by much. The engine Torque Curve (as a function on speed) , not just the peak number, is very important in how useful the an engine will be for it's intended application.

So if I understand what you said then the torgue increases in my toyota the slower the engine is running. That means then at 100 rpm I have more torque out of my kubota than I have at 1000 rpm. I dont understand how that could be. Seems to me that I would have more torque the faster my engine turns. Theoretically if I could get my engine to run at 1rpm it would have the most torque it will ever have ?

 

[KICK]

None of the equations are seasonal.

no they aren't.

but people are.

whole discussion is off the wall.
its all about numbers.
numbers don't lie.
people do.

some people don't seem to believe the numbers.

You cant help them.

 

[Egon]

Goodness sake John, don't believe everything I say. Sure hope you didn't bang the finger and have it fall off due to brittle failure.

Up here it's so darned cold that when I went to start the fire the match flame froze!

A diesel with torque: Image attached.