Assume diesel and gasser have same torque, compare...

If they have the same torque then they also have the same HP.

The guy with the 50% more HP would have a beer drank and maybe a 6 pack before the other guy got to the top of the hill.

Gas, diesel, electric, steam or actual horse power; it does not matter. HP wins because of the time factor.

Hi,

You stated that both would have roughly the same amount of "Torque".

It is torque X RPM's that make up horsepower. So despite that gas engines now typically have less torque than a diesel, they make as much horsepower due to their ability to turn 5,000 RPM for long periods of time on a test bench in a lab.

While I have run my 460" motorhome engine at 4,200 RPM while climbing a mountain, it has a longer stroke and probably should not run that fast a long time. The much smaller pistons in a 5.4L or 6.8L v10 would be happy running 4,200 RPM for 5-10 minutes at a time, even go to 5,000 RPM for a minute or two. That engine is designed that way.

The reason Ford went with a V8 configuration in the trucks is it can run higher RPM's than the straight 6 diesels that Ford has built for over 80 years. Even back in the 60's Ford teamed up with Caterpillar to build the Ford 636 diesel, a V8 that was not turbocharged. Later turbocharged engines where much more powerful, but Ford wanted something to put in their class 7 and class 8 trucks besides the normal inline 6.

So given you want to "Race" a early 7.3L diesel engine with a lower factory torque rating to the later versions of say a 6.8L gas engine with about the same torque rating, and yet much higher RPM ability, yes the gas truck will run to the top of the mountain faster. Or of you like to compare GMC's, then take a 6.2L diesel and run it against a 350" gas engine, and the gas engine will win all the time, due to higher HP rating.

However if it is a contest to run from Los Angeles to Las Vegas, and both have 35 gallons of fuel, and any fuel stop requires them spending 35 minutes at the fuel stop, then the diesel can win that "Race" by taking the hills a little slower and saving fuel. Running a little faster on the level and downhill sections will not cost to much fuel, and will save time overall. The extra minute you spend at 45 MPH going up the two or three major mountain passes will be made up in time saved buying fuel.

Fred.

I'll still be at the campground before you. Your specific narrow hypothetical situation might beat me to the top of the pass but you'll have a hard time passing a gas station.

And Go BA Tigers! Class of 88

therink wrote:

2oldman wrote:
Hoo boy, I'll get the popcorn.

I think we all need warmer weather so we can go camping.

X2 to that, but here is a short answer.

Well to get a diesel with as little torque as a gasser, would need to go back to a 12 valve late 80's and early 90's Cummins ISB. This is the lowest rated Cummins.
HP 160
Torque 400

The NEW Ford 6.2, is a close match for torque.
Horse power
385 @ 5500 rpm (Super Duty <10K GVWR)
316 @ 4179 rpm (Super Duty >10K GVWR)
Torque
405 @ 4500 rpm (Super Duty <10K GVWR)
397 @ 4179 rpm (Super Duty >10K GVWR)

So it only took gassers 20+ years to catch up on torque.
Well let's do current to current
Cummins 6.7 (2013)
350 hp @ 2,800 rpm
850 lb-ft @ 1,700 rpm

If I was buying new NO Question what I would buy.

This is an easy question, the way it has been presented. Justlabs is 100% correct. This discussion will be full of ignorance, but there is one and only one answer. The vehicle with the most "POWER" wins. Not only that, but torque is 100% irrelevant.

However the statement of a 1000 rpm difference is far off. The rpm difference is likely to be 4000 or more. I would not want to have to whip out the CC for the gas vehicle in this scenario. The cost per 1000ft of elevation gain will be double or triple in the gas truck.

2oldman wrote:
Hoo boy, I'll get the popcorn.

I think we all need warmer weather so we can go camping.

Hoo boy, I'll get the popcorn.

The gas engine making 50% more HP would be waiting for the diesel at the top of the grade.