What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

discussing cummins vs 6.2 6.5l

I will start with an off topic comment just to show you why I like I6:
I have a 12 litre CAT in my big rig, it has 1650 lbs of tq and 430 hp, the truck weighs 17000 lbs and I get about 13 MPG, when I hook up my empty trailer to it 17000 lbs for a total of 34000 lbs I get about 8-9 MPG.
Loaded to my max, 80000lbs, I get 7.5 MPG.
My friends are getting those MPG numbers from their 5.9l cummins pulling the 10000 lbs trailers.
Since I found that out I ditched my pickups and use my rig to pull any trailer I have.
I only kept my suburban and blazer chalet.:D
 
jonrpick said:
Um... that's what I said... Your logic is the same as mine.

It will take "X" amount of fuel to support "Y" horsepower, regardless of displacement. Yeah, I know you could probably make an engine much smaller than 2.0L hit those numbers if you could spin it fast enough.

And durability was never part of my question. I know the 2.0L won't survive long under those conditions... It was about comparing the differences in design between a 6.2/6.5 and 6BT. I understand what's being said regarding more fuel=more power in a diesel, but that holds true for gas motors too.

Now, having said that... How would a 6BT compare if it were just a 6B--with no turbo? In N/A form, would the power levels be more comparable with the 6.2L V8?

I may need to start another thread... this is veering off the main topic of the thread... :doah:
Click to expand...

Yes, an NA 5.9 Cummins will be roughly the same power-wise as a NA 6.2 or 6.5. Actually, the 6.x motors have a bit better volumetric efficiency in NA form since they have more valve area in the form of 2 extra cylinders, so they should be able to burn a tad more fuel.

In terms of efficiency and mileage, the direct injected Cummins should be a bit more efficient than the indirectly-injected 6.x, but there are a lot of variables at work. How the engine is set up, especially regarding timing, makes a big difference.

For the friends of iceman getting really low MPG numbers in their Cummins, how are they managing to do so badly?
 
I was talking to a guy a few years back that pulled a large horse trailer with living quarters to rodeos all around the West and he used a 4dr powerstroke to do it. He said he would get 8-9 pulling and even lost his tranny once in the middle of no where. He ended up buying a used big rig to pull with and would get around 11-12 with way more pulling and stopping power.

I knew the big rigs were at around 400 -500 hp but had no idea they produced 3-4 times that in tq.:D
 
MaxPF said:
Yes, an NA 5.9 Cummins will be roughly the same power-wise as a NA 6.2 or 6.5. Actually, the 6.x motors have a bit better volumetric efficiency in NA form since they have more valve area in the form of 2 extra cylinders, so they should be able to burn a tad more fuel.

In terms of efficiency and mileage, the direct injected Cummins should be a bit more efficient than the indirectly-injected 6.x, but there are a lot of variables at work. How the engine is set up, especially regarding timing, makes a big difference.

For the friends of iceman getting really low MPG numbers in their Cummins, how are they managing to do so badly?
Click to expand...

Like sixb stated, they pull heavy loads all the time.
I saw a guy pulling a 25k trailer and he was getting 6 MPG.
He bought the 4500 dodge for business. H epulls a 35' flat bed trailer.
The only advantage he has is registration, I pay $2500 a year he probably pays $500- $800.
 
MaxPF said:
Yes, an NA 5.9 Cummins will be roughly the same power-wise as a NA 6.2 or 6.5. Actually, the 6.x motors have a bit better volumetric efficiency in NA form since they have more valve area in the form of 2 extra cylinders, so they should be able to burn a tad more fuel.
Click to expand...


Whew....its a good thing they never made a N/A cummins B series then isn't it :bow:
 
imiceman44 said:
I will start with an off topic comment just to show you why I like I6:
I have a 12 litre CAT in my big rig, it has 1650 lbs of tq and 430 hp, the truck weighs 17000 lbs and I get about 13 MPG, when I hook up my empty trailer to it 17000 lbs for a total of 34000 lbs I get about 8-9 MPG.
Loaded to my max, 80000lbs, I get 7.5 MPG.
My friends are getting those MPG numbers from their 5.9l cummins pulling the 10000 lbs trailers.
Since I found that out I ditched my pickups and use my rig to pull any trailer I have.
I only kept my suburban and blazer chalet.:D
Click to expand...

How many gears in your big rig? That'll be your primary difference right there . . . Your average pickup truck driver wants to tow like a big rig but still do nothing but steer, and that's where the fuel mileage goes.

Leave a Cummins in stock form, with it's 900RPM power band :haha: and put 13 or 18 gears behind it--bet you'd be amazed at the fuel mileage towing.

Air suspension that can be adjusted to the load, and G or H rated tires running at 110PSI probably make up the rest of the difference . . . .
 
MaxPF said:
For the friends of iceman getting really low MPG numbers in their Cummins, how are they managing to do so badly?
Click to expand...

they are probably being honest. since many people i know lie about MPG.
 
i know plenty of people who put a programmer on and SWEAR by the overhead display...
 
You must log in or register to reply here.

Latest Posts

Top Bottom