Originally Posted By: another Todd
Originally Posted By: edhackett
Originally Posted By: RangerGress
It's so obvious to me that the difference in tow ratings (~2500lbs) between ED and Hemi is due almost entirely to the engine that I don't understand how anyone could be unconvinced. The Hemi is almost twice as powerful as the ED (395hp vs. 240). Drag racing up the side of a mountain that would make a helova difference.
RangerGress wins the cookie. Horsepower is a time based measure, as is speed. Higher hp means the same work done in less time.
I've run some numbers for tractors that will serve to illustrate:
I've got a 1941 John Deere B rated at 18.5 hp at 1150 rpm which equals 84.49 ft/lbs of torque. The Kubota L5060 is rated at 44 hp at 2700 rpm which equals 85.59 ft/lbs of torque, the same as the JD for practical purposes. Were you to attach both to a plow that took 2700 lbs of force to move, the JD would be able to plow at 2.55 mph, the Kubota at 6.1 mph.
The EcoDiesel has the same torque as a HEMI(right between the 5.7 and 6.4), but due to it's lower horsepower, takes more time to do the same work. It can pull as much as a HEMI, but must do it at a lower speed, or pull less at the same speed, 40 mph in the case of J2807.
Ed
P.S. Very happy new EcoDiesel owner here. I'll post my impressions in the next couple of days in the Vehicles sub forum.
If this is true, why are diesel pickups (towing a load) passing everything else (towing a load) on the hills. Load down a gas engine and it just cannot compete with the diesel. Not saying it won't do OK, just that the diesel will do better.
Two reasons for this in modern light duty pickups.
1. Diesels are typically boosted, at higher elevations boosted engines are better able to maintain their HP ratings. At 9k feet your Hemi is probably only making 290hp or less, where as a 6.7L Cummins once on boost is making its full 400 or whatever the new ones are rated at.
2. In this case the Hemi has 410ft pounds of twist, the Cummins has I believe around 900. That's how you get up hills.
Back in the 80's and earlier it was reversed, diesel technology was not up to speed so large gas engines were much more powerful and passed them up the hills.