โFeb-14-2020 07:36 AM
โFeb-19-2020 09:20 AM
โFeb-19-2020 09:03 AM
โFeb-19-2020 07:53 AM
โFeb-19-2020 06:55 AM
FishOnOne wrote:
I think we have already seen a preview of what the 2020 HO cummins will do. It was essentially a tie with the Duramax although some will argue it was a DRW therefore packing more weight.
What I'm really interested in is the HO cummins fuel economy towing 30k at this point.
โFeb-17-2020 11:34 AM
rjstractor wrote:RoyJ wrote:
If you read his post again, it's flat *power* curve, not torque curve.
A falling torque curve is desirable in a heavy duty motor, because as you lug down the revs in a gear, you get torque rise, thus fairly constant power.
The Cummins loses less power at lower rpm than the Duramax, and thus won't need 10 speeds nearly as much.
Exactly, the motor with the flat power curve maintains horsepower when shifting to the next higher gear, whereas the motor with a flat torque curve loses horsepower with every shift. The extra gear ratios help minimize this.
โFeb-17-2020 08:24 AM
rjstractor wrote:RoyJ wrote:
If you read his post again, it's flat *power* curve, not torque curve.
A falling torque curve is desirable in a heavy duty motor, because as you lug down the revs in a gear, you get torque rise, thus fairly constant power.
The Cummins loses less power at lower rpm than the Duramax, and thus won't need 10 speeds nearly as much.
Exactly, the motor with the flat power curve maintains horsepower when shifting to the next higher gear, whereas the motor with a flat torque curve loses horsepower with every shift. The extra gear ratios help minimize this.
โFeb-17-2020 07:01 AM
RoyJ wrote:
If you read his post again, it's flat *power* curve, not torque curve.
A falling torque curve is desirable in a heavy duty motor, because as you lug down the revs in a gear, you get torque rise, thus fairly constant power.
The Cummins loses less power at lower rpm than the Duramax, and thus won't need 10 speeds nearly as much.
โFeb-17-2020 12:13 AM
wilber1 wrote:
The last Cummins to have a flat torque curve was the 350 HP 650 LB/FT. in early 2011
It reached 650 lbft at 1600 RPM and stayed flat until peak power at 2800 RPM
The 350/800 engine reached 800 lbft at 1600 RPM but gradually decreased until it was the same as the 650 engine at 2800 RPM. If it was still making 800 lb ft it would be putting out 426 HP, not 350.
If the Cummons 900 engine was still making 900 lb ft at 2800 RPM it would be putting out 480 HP, not 385.
โFeb-16-2020 08:58 PM
FishOnOne wrote:
I think we have already seen a preview of what the 2020 HO cummins will do. It was essentially a tie with the Duramax although some will argue it was a DRW therefore packing more weight.
What I'm really interested in is the HO cummins fuel economy towing 30k at this point.
โFeb-16-2020 03:22 PM
FishOnOne wrote:
I think we have already seen a preview of what the 2020 HO cummins will do. It was essentially a tie with the Duramax although some will argue it was a DRW therefore packing more weight.
What I'm really interested in is the HO cummins fuel economy towing 30k at this point.
โFeb-16-2020 01:27 PM
โFeb-16-2020 01:15 PM
โFeb-16-2020 07:47 AM
โFeb-16-2020 07:16 AM
Grit dog wrote:
Wishes for best possible outcomes in your life Larry. Sounds like you both have been able to enjoy the better things in life for more than a while and that is priceless.
โFeb-15-2020 09:41 AM