2025 Ram trucks

[Blue Mule]

There is no gasoline engine that I've seen, turbo charged or not, that makes 3 times the torque value vs. horsepower the way that a diesel does. My uncle was just commenting last night about how he accidentally pulled into a ditch in the snow. His Cummins just idled itself in reverse out of the ditch. With a gas engine, RPM would have needed to be much higher to provide the torque to back out...in other words you can get the same tire motion with little to no throttle input on a diesel. That's why they are more fuel efficient...they don't need high RPM. It has more to do with piston stroke and compression ratio which are both greater in a diesel engine.

 

[nisaacs]

Off idle torque/clutch engagement torque, one and the same.

B6.7 is 400, 6.4 Hemi has a maximum torque of 429...

https://www.cummins.com/engines/b67-2021#tab-navigation

 

[Snobdds]

There is no gasoline engine that I've seen, turbo charged or not, that makes 3 times the torque value vs. horsepower the way that a diesel does. My uncle was just commenting last night about how he accidentally pulled into a ditch in the snow. His Cummins just idled itself in reverse out of the ditch. With a gas engine, RPM would have needed to be much higher to provide the torque to back out...in other words you can get the same tire motion with little to no throttle input on a diesel. That's why they are more fuel efficient...they don't need high RPM. It has more to do with piston stroke and compression ratio which are both greater in a diesel engine.

I bet next you'll tell me a 6.7 can produce more power than a 3.5 liter engine.

Of course what you said is true. It's all obvious to anyone with a room temp IQ that has driven both a diesel and a gas engine.

What I'm failing to understand is...what is off idle torque?

Furthermore, your getting stuck example. Just last weekend I was parking the truck in a ski resort lot that had a slight pitch down. As soon as I pulled in I felt the weight of the truck shift to the front. The rear end had zero weight on it. So how does one get out before spinning the tires to create an ice spot under the tires? All I did was put my foot on the break and apply off idle torque to trick the torque management and the traction control to think the spinning wheels had zero traction and it would shift the power to the wheels with traction. I showed the kid how to be smarter than a microchip.

 

[Topzide]

They also added a 7th injector to the emissions system instead of fueling the cylinders to get it "hot".

 

[dieselscout80]

I bet next you'll tell me a 6.7 can produce more power than a 3.5 liter engine.

Of course what you said is true. It's all obvious to anyone with a room temp IQ that has driven both a diesel and a gas engine.

What I'm failing to understand is...what is off idle torque?

Furthermore, your getting stuck example. Just last weekend I was parking the truck in a ski resort lot that had a slight pitch down. As soon as I pulled in I felt the weight of the truck shift to the front. The rear end had zero weight on it. So how does one get out before spinning the tires to create an ice spot under the tires? All I did was put my foot on the break and apply off idle torque to trick the torque management and the traction control to think the spinning wheels had zero traction and it would shift the power to the wheels with traction. I showed the kid how to be smarter than a microchip.

I only guess his meaning, but I would take it to high torque at low RPMs aka just above idle RPMs.

Straight six cylinder engines are known for having more torque at lower RPMs than V8s.

 

[Snobdds]

I only guess his meaning, but I would take it to high torque at low RPMs aka just above idle RPMs.

Straight six cylinder engines are known for having more torque at lower RPMs than V8s.

Like I said earlier...It's the turbos that do that.

Straight six's are more efficient about getting the exhaust to spool the turbo than a V8. The down side to that is a straight six is spooled out faster than a V8, meaning a straight 6 runs out of air well before a V8. The top end of a straight 6 is lower than a V8.

So, which one is better?

Also this is a debate the Hay man and I have had for years. He was chumming the waters for me.

 

[Hay Dude]

Have you looked at a dyno for a boosted gas engine? How is that any different than a inline 6?

It’s not.
I guess I assumed you were talking about V-8s and the ongoing comparisons you and I make between the in-line 6 and the V-8.

 

[Hay Dude]

Maybe, just maybe...off idle torque is created based upon how fast a turbo spools up?

Just spitballing here.

It can be. Ford makes sequential (not dual) turbos on their 6.4L V-8 diesel.
That helped the V-8 get spooled up faster, but made the turbo set-up more complex, unreliable and expensive.

 

[Hay Dude]

Like I said earlier...It's the turbos that do that.

Straight six's are more efficient about getting the exhaust to spool the turbo than a V8. The down side to that is a straight six is spooled out faster than a V8, meaning a straight 6 runs out of air well before a V8. The top end of a straight 6 is lower than a V8.

So, which one is better?

Also this is a debate the Hay man and I have had for years. He was chumming the waters for me.

But I maintain a in line 6 makes more torque at lower RPM than a V-8. They always have.
Then there’s the greater bearing support and all the other advantages, but we won’t go into that.

 

[Snobdds]

It can be. Ford makes sequential (not dual) turbos on their 6.4L V-8 diesel.
That helped the V-8 get spooled up faster, but made the turbo set-up more complex, unreliable and expensive.

I think we just discovered off idle torque is a function of turbo efficiency through the RPM band.