Diesel vs gas......................

Madhatter1 wrote:

Hannibal wrote:
You need to put it into perspective. A 350 hp tractor engine running at it's peak hp rpm of 1800~ is at it's peak hp rpm. A 350 hp SB gas V8 in a pickup truck running 1800 rpm is almost 4k rpm under it's peak hp rpm and is likely making less than 120 hp.

If you think those 350HP enines are equal for moving a big load you are way off. The tractor is over 1000 lbs torque at 1800 and the gas is at 300 lbs at 4K (using your example numbers). Another BIG factor is the tractor is makeing big HP numbers at lower RPM's and the peak torque is going to be much higher than 1K. You guys are doing a dis-service to posters looking for info on gas vs Diesel. Even if us Diesel guys post they are not as fuel efficient, as reliable, or as cost effective as they used to be the gas fans still neeed to say "mine can pull the same load through gearing". Might be able to do the job (which is an inportant fact for those that need a truck more for a daily driver than towing) but a low RPM Diesel has a big advantage pulling a load. Get off your high horse and talk facts to help out posters looking for some real world info. I drive a 4X4 3500 Dually Diesel but can recognize that is not what everyone else needs. I pull a 14.5K to 15K trailer all over. Off road a lot. Still not gonna tell someone who pulls the same load 100 miles to a paved campground they need the rig I went with. And you "engineer math guys" need to drive a truck with a load on it. Your calc's do not work out in the real world. If they did a pair of 260HP 350CI gas engines could equal the 260HP Cummins 360CI in my boat. They would never be expected by any marine designer to even get the boat to plane off. What??? I thought HP was HP. 350 HP at 1800 RPM in a whole different animal than 350HP at 4K or 5K. Flame away.

They have been talking facts, and proven science backed up with math. If it werent for things like math and science and engineers, you wouldn't have your truck to begin with.

I have seat of the pants experience with high horse power and high torque engines in light duty vehicles. I love the feeling of a high torque motor and agree, it does have that "seat of the pants" benefit.

Still, max output power (Horsepower) is just that. It's the most you have. If you are powering down the highway or up a mountain, you are now in the realm of horsepower. That's why they make larger horespower OTR truck engines for more demanding applications. If two engines of any kind were in two identical trucks going up the same infinite uninterupted incline pulling the same load, whichever one had more horsespower would eventually go faster.

This even works comparing two diesel engines. The one with more horsepower will be capable of a higher top speed not matter the torque.

I've posted this quote before and I will post it here again:

From Diesel Power Mag:

http://www.dieselpowermag.com/features/1111dp_king_of_the_hill_rematch/viewall.html

"
The first time we put the 800-lb-ft Ram into gear, the extra torque felt obvious. We found ourselves checking to see if the transfer case was in low range. Yet when we got up to highway speeds, a few things became clear. The first was that even though the Ram matches the Ford (and beats the GMC) in torque production, towing this much weight at highway speeds is a test of horsepower—not torque. The Ram showed its 50hp deficiency attempting to keep up with the Power Stroke and Duramax everywhere we went."

I know no one wants to listen to some silly "Math engineer guys" on a forum but something tells me the people at that publication kinda know what they are talking about.