5.9 peak torque

[Parkerco]

Just got a 2000 Discovery with the 5.9 Cummins/275hp w/Banks Power Pack. Question is: according to the data plate the max rpm is 2500 which I assume is the governed rpm but I can find no info as to the peak torque rpm. My preveous '93 5.9 pretty much peaked at about 1600 rpm so I assume this one is the same. Anybody know for sure?
Also, do most of you try to keep your rpm's at peak torque when climbing steep grades or do you run a little higher, like maybe 2000 rpm or so.
Thanks - Harv

[sc3283]

Banks will be able to give you the best info on peak torque rpm

[Wizard]

Harv, what transmission do you have. I've been told that my MT643 can't handle a banks upgrade.

[RustyJC]

Quote:

Originally Posted by Parkerco Just got a 2000 Discovery with the 5.9 Cummins/275hp w/Banks Power Pack. Question is: according to the data plate the max rpm is 2500 which I assume is the governed rpm but I can find no info as to the peak torque rpm.

That's interesting as the 5.9L HO in the Dodge Ram application made 245 BHP @ 2700 RPM and 505 lb-ft @ 1600 RPM with fuel shutoff ~ 3250 RPM. The torque curve was controlled by the ECU and was absolutely flat from 1600 - 2700 RPM due to maximum allowable drivetrain torque limitations imposed by Dodge. See the curves attached below.

After "bombing" it with an Edge EZ and bigger injectors, the ECU limit to the torque curve was overriden, and the engine made 347 BHP @ 2700 RPM and 762 lb-ft @ 2200 RPM at the rear wheels. My point is, if the Banks Power Pack similarly removes the ECU-imposed torque limits, you might see your torque peak move higher in the RPM band. Perhaps Banks can provide you some dyno graphs for their kit.

Rusty

[Parkerco]

I have the 3000 series 6 spd tranny. Good thought though on asking Banks. Didn't think about the fact that their power pack would most likely change the torque curve. I'll check with them on Mon and let you know.
What about the hill climbing thing? Do you guys run a little higher rpm just on general principles or do you watch the EGT's and run accordingly?
Harv

[bluepill]

My ISB 6.7 is flat 750 torque from 1600 to 2600. To maximize both air (CAC), water, and trans fluid cooling, I downshift to keep the RPMs in the 2000-2400 range when going up serious hills. That's one of the great things about the Allison 3000.

[J Walker]

Here is some information from a Cummins Tech Sheet on my 2000 ISB 260 HP. My peak torque is 550 ft-lb from 1900 RPM to 2400 RPM. Torque fall off is gradual below 1900 RPM and operation at 1500-1600 RPM works well. I aim at 1600 RPM for fuel economy. You should be able to get a tech sheet for your engine by calling Cummins at 1 888 769 3778. Banks has altered the torque curve so you should contact them also. It would be interesting to compare the Cummins and Banks curves. Send me a private message with your email address and I can send you my tech sheet.

[Sonnydale]

Harv,
I have the same setup as you but in a 01 Bounder. According to banks, highest torque is 803 lb-ft @ 1700rpm. The torque curve then goes down to 775 lb-ft @ 2300rpm which is still much higher than the stock 660 lb-ft @ 2300rpm.
I try and keep mine at around 2000rpm as to me it feels where it has the most power.

Sonny.

[Parkerco]

Thanks for the info. Will call Cummins and Banks on Mon and see what I can find out. Will let you know.
Later - Harv