Does the 6.7 really make more torque than the other 2

[SAP2018]

Just curious, always read that the 6.7 makes more down low torque, not to mention I see at least 60-70% of trucks towing big stuff having 6.7 Cummins in them.

I drive up and down the 5 weekly from LA to SF and can’t help but analyze. I love my Cummins , I’m a Chevy guy but a duramax looked pretty intimidating under the hood, Powerstroke...although powerful, I could NEVER buy a ford! (My wife and kids would kill me)

 

[EricViviano]

I can't speak for the Duramax, don't know anything on them past the LLY motors.

But have seen quite a few cowboys around here go to the new Fords from Cummins and love them. Haven't heard one say yet they wish they wouldn't have. But two thing stood out to me when shopping for an 18 model truck. The Ford was 10K more for same thing, and they are just too fancy for me inside. And to be honest I wanted the manual trans, so RAM was the only option.

 

[EricViviano]

@SAP2018 - Side note = How are you running deleted in California? They failed my Dad's 03 7.3 Powerstroke because he had a Garrett GTP38 turbo.

 

[Wayne M.]

Bottom line, nothing beats the grunt of a long stroke in-line 6. Compare the torque curves of the 3 at 16-1800 rpm. Cummins is the king of grunt.

 

[TFucili]

In fairness, the V-8s have closed the gap in recent years, and a quick search didn't turn up comparative torque curves for the current version of each, BUT inherently the tall deck, long arm design of the Cummins will tend to produce a broader spread of torque. Peak numbers are great, but surfing that torque curve is what gets you up the hill.

 

[Wayne M.]

That’s right TF. the other 2 don’t want their full torque curves, off idle known. Lol.

 

[SAP2018]

@SAP2018 - Side note = How are you running deleted in California? They failed my Dad's 03 7.3 Powerstroke because he had a Garrett GTP38 turbo.

Smog is not a problem for me in California, never has been. Just gotta know the right people.

 

[EricViviano]

Smog is not a problem for me in California, never has been. Just gotta know the right people.

What if you get pulled over? The CHP would they be as kind?

 

[TFucili]

That’s right TF. the other 2 don’t want their full torque curves, off idle known. Lol.

Out of pure curiosity, I would like to see all three torque curves side by side, and all in the same scale, so no phony shaping going on. The new L5P(?)appears to be pretty stout.

 

[SAP2018]

What if you get pulled over? The CHP would they be as kind?

Who knows, but a few of the sheriffs and CHP officers I know also drive deleted trucks, maybe they will find out also when they get pulled over.

I have a muffler on my truck and don’t drive like a jackass, in 20yrs of driving “illegal” modified vehicles I have never had an issue, It’s worse to speed down the road, be on a cell phone, or drive drunk (all of which I don’t do) than drive a modified vehicle by someone who respects road laws.

 

[SAP2018]

Out of pure curiosity, I would like to see all three torque curves side by side, and all in the same scale, so no phony shaping going on. The new L5P(?)appears to be pretty stout.

Back to the topic...yes the L5P is the one that caught my eye, but when I was shopping and researching they were barely rolling out and I wasn’t comfortable buying that new of a motor, the Cummins is tried and true, down on power but with 800+ lb ft of torque...I can’t believe we complain sometimes.

 

[DonFitzwater]

Out of pure curiosity, I would like to see all three torque curves side by side, and all in the same scale, so no phony shaping going on. The new L5P(?)appears to be pretty stout.

That would be a good comparison to see what the horsepower and torque curves look like when splattered all over a dyno chart.

I can tell you exactly what a Ford F350 Lariat looks like with the cab off and engine scattered all over the diesel tech service bay...............I have no idea how my Ram looks in that state, thankfully.

 

[AH64ID]

That’s right TF. the other 2 don’t want their full torque curves, off idle known. Lol.

It's been a while since I've seen a published Cummins torque curve as well. It's not as flat as it was with the 5.9.

That's not saying it's bad thou.

The 325hp 5.9 only lost 22 lb/ft from peak torque thru peak hp.

The 2018 6.7 loses 208 lb/ft from peak torque thru peak hp.. that being said at peak hp it's still making 722 lb/ft. The 2019 loses 250 lb/ft in the same rpm range.


If you look at the 2018 specs they are really not all that different in the normal rpm band. The DMAX and Powerstroke do hold more power in the upper rpm band thou, which is not uncommon with V-8 vs I-6.

2018 Ram
Aisin 301/930 @ 1700; 385/722 @ 2800
68RFE 258/800 @ 1700; 370/694 @ 2800
G56 188/660 @ 1500; 350/656 @ 2800

2018 Ford
320/935 @ 1800; 450/844 @ 2800

2018 GM
277/910@ 1600; 445/834 @ 2800

2019 Ram
Aisin 342/1000 @ 1800; 400/750 @ 2800
68RFE 275/850 @ 1700; 370/694 @ 2800

As you can see the RPM ratings for torque are all different. I'd be curious to see what the torque on the 2019 Cummins is at 1700.

The I-6 with the VGT really does shine at lower rpms when loaded.

 

[Wayne M.]

I don’t think the Ford 6.7 cabs come off nearly as much as the old 6.4’s did. That’s a life I live.

 

[EricViviano]

I don’t think the Ford 6.7 cabs come off nearly as much as the old 6.4’s did. That’s a life I live.

The 6.4 is the biggest piece of garbage diesel engine ever developed, even surpassing the legendary 6.0. They spin main bearings, for no reason, rendering the block scrap iron.