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-   -   610lb-ft - 800lb-ft Why did the Manuals get Left Out (http://www.ramforumz.com/showthread.php?t=154546)

Blownsquidink 10-01-2013 11:32 PM

610lb-ft - 800lb-ft Why did the Manuals get Left Out
 
I just bought a 2011 2500 4x4 with a 6.7l cummins and a manual 6 speed. Only to find out that I'm down almost 200 lb ft of torque from and automatic truck. Does anyone have a clue why? And an even better question, what's the differences between the two engines, so I can get the hp and torque a manual deserves...

scrappy 10-02-2013 03:04 AM

Quote:

Originally Posted by Blownsquidink (Post 1212497)
I just bought a 2011 2500 4x4 with a 6.7l cummins and a manual 6 speed. Only to find out that I'm down almost 200 lb ft of torque from and automatic truck. Does anyone have a clue why? And an even better question, what's the differences between the two engines, so I can get the hp and torque a manual deserves...

because the G56 manual is marginal behind the Cummins in some situations. so they de-rated the engine to help it live. IMHO when they dropped the NV5600, they stopped selling a manual that I will own!
If I want a manual, than I will retrofit a roadranger in!

brandonjansen 10-02-2013 12:33 PM

Yes pretty much what scrappy said. The manual Cummins are de-tuned because the G56 is not capable of handling the torque. That being said, it's very easy to get it tuned back up.... Any aftermarket tuner will bring it right back up to where an automatic would be tuned (at least that's what I've read). So a manual truck actually gains more out of a tuner than an automatic does. If you do that, just be prepared to have your tranny rebuilt and to be putting a better clutch in it.

Take a look at H&S Performance. They make great tuners for Cummins.... the one issue you might run in to is the fact that you live in Cali.... Not sure what the rules are there regarding the H&S Street Tuner.

Blownsquidink 10-03-2013 07:37 PM

Awe Balls!!! That crap. Manuals are supposed to be as strong if not stronger than an automatic. I was told that it was because of the power it took to push an automatic, that's why theirs were higher. Anywayz, I was looking, and the hp is the same just the torque is high between stock trucks. Howz that possible. Due to I wanted to put hard parts in the engine instead of messing with the EDC. Or is that what the factory did??? Did they just change the programming at the factory??? If I was to go with a programmer, which one is the better bang for the buck??? I've heard alot about "EDGE" programmers. Your thoughts

brandonjansen 10-03-2013 10:00 PM

It used to be that way, apparently not anymore. But part of it could be to do with turning the automatic as well. I'm sure it doesn't take 150 ft-lbs to turn a 68rfe though.

You want to start with a tuner for sure. You need one of those to even start doing engine work. H&S Performance makes the best tuners for 6.7 Cummins. But with all the stuff going on with tuners and the EPA now it's getting more and more difficult to find a "race tuner" capable of deleting. Plus the prices have sky rocketed. You're looking at around $1600 for the tuner. Then you need an EGR delete and DPF delete kit. From there you can start doing more engine mods like head studs, intake horns, turbo's etc.

kerton 10-08-2013 04:00 AM

"Manuals are supposed to be as strong if not stronger than an automatic."

Guys, vehicles have changed a lot since we learned the rules of thumb. Used to be a manual transmission was faster, offered better HP torque and towing, and had better fuel mileage. No more.

Basically, they have made machines that just shift better than humans can. That's why sports cars (ex: Ferraris) are now forgoing the manual to actually improve performance.

Here's what's changed:
- Automatics have locking torque converters, or even just automated clutches. The TC is where lots of slop and bad fuel economy lived, so it's going away.
- Automatics are adding more gears. This keeps your engine closer to optimal RPMs.
- Automatics can shift much faster, reducing the times when then engine is doing no work

Here's reference:
http://www.edmunds.com/fuel-economy/...ck-shifts.html

Of course, in your particular case, it's just that the manual wasn't designed to handle the 800 foot pounds the engine can produce, so they de-tuned the engine. Yes, you can chip it to get the torque back. In fact, there are VERY few vehicles that can get as much out of a chip as you. It's not sorcery to extract more power from an engine that is governed! but, as said, that torque can bust up your tranny if you abuse it.

kerton 10-08-2013 04:18 AM

"Anywayz, I was looking, and the hp is the same, just the torque difference is high between stock trucks. Howz that possible?"

You gotta learn what exactly torque and HP are, and how they are related. You're not alone. I think this is the most misunderstood duo among truck enthusiasts. Lemme see if I can explain it fast and easy:

HP is the POWER that your engine can produce, which varies at different RPM, and maxes out at the peak of the HP curve which is below the redline. At that RPM, your engine is capable of doing the most work - be it climbing a hill, accelerating, PTO, or whatever.

Torque is (very basically) your POWER *per revolution*. If your vehicle can produce a fair amount of power at low RPMs, it will have good torque.

High torque is what will break your tranny. That's the force that's twisting it, not high HP. At peak HP, say 3000 rpm, your engine is cranking out max POWER to the wheels, but the power is being spread across many rotations, so torque is lower. Therefore, Dodge didn't need to limit the engine's HP, but they did need to limit its torque.

BTW, here is a small consolation: despite that you (and I, with my 2011 Cummins auto) only have the 650 max foot pounds of torque, we actually have just about the flattest torque curve of anyone out there...because we're being governed to 650. That means we have access to our full torque at just about any rpm. It actually feels pretty good to drive. Now, of course, the guys with 800 have got more, but their torque curves are not flat like ours. They peak to 800 at a specific rpm only, and in fact, spend much of the rpm chart at torque below 800 and closer to us. Small consolation, as I said.

Blownsquidink 10-08-2013 11:09 AM

Hey, thanks a lot for your replies. I kinda understand hp and torque. But from a gas engine stand point. And what I still dont get is, how can the hp be the same but the torque different between two of the same engines. Does the automatic engine come with longer rods or a different crank? The reason I'm so rapped around the axle (no pun entended) about this is. I really don't wanna run with a programmer. With the truck only being a 2011 and only 22,000 miles, I still have a lot of warrenty left and I don,t wanna give Dodge any reason to back out of any repairs. And agin I really do appreciate all of your replies. Please keep a look out for me, because the longer I drive this thing I keep coming up with more and more questions.

dodge man 10-08-2013 11:35 AM

The difference in torque is just in the tuning. Its probably holding fuel out and boost out to keep the torque numbers down.

kerton 11-15-2013 01:19 PM

De-Tuning and Governing
 
"how can the hp be the same but the torque different between two of the same engines?"

As DodgeMan said, it's just the tuning of the engine from the ECU (computer), or in our case, de-tuning of the engine. The main trick that's fooling you is that peak torque and peak HP happen at different rpms. At peak torque, 1600 rpm, your 2011 engine is deliberately governed, while at peak rpm, 3013 rpm, it is not. The 2012 is not governed in this way.

Our engines, the 2011s, are physically about the same as the 2012. Here's how the ECU can make torque different, but HP the same:

- up to about 1500 rpm, both engines have the same power and HP, both reaching 650 ft-lb of torque. Since the 2011 tranny is only specced for 650 ft-lb, the 2011 ECU will now begin delivering less fuel to the injectors as rpms grow to hold torque to 650. The 2012 is not limited, so will deliver more fuel, and more HP, and more torque than the 2011 as rpms grow.

- at 1600 rpm both engines are capable of something close to 800 ft-lb or torque, but the 2011 is governed and still flatlined at 650 ft-lb, while the 2012 is at peak torque of 800. The 2012 torque will begin dropping as rpm goes up. The 2011 torque does not drop as rpms increase, it will stay at 650.

- at 2800 rpm, the 2012's torque has dropped from its peak back down to 650 ft-lb. The two engines now perform exactly the same again, and will continue to do so as rpms increase. The 2011 is no longer governed or limited, since torque is falling below 650 naturally because of standard engineering principles.

- at 3013 rpm, both engines perform exactly the same and reach peak power, with 350HP. Power will now decrease as rpms go up, so don't do that.

See these torque/HP curves for both engines:

http://www.cumminsdieselspecs.com/67.html

When you look at them, it's kind of a bummer that they didn't keep the same labels and scale. So just look at the right one, which is the 2012. Imagine that the 2011 is also on that graph, then the 2011 would look exactly the same...except the torque curve would look like a mountain with the summit sliced off horizontally at 650 ft-lb.


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