4x4ord
Alberta
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Joined: 12/23/2010
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Huntindog wrote:4x4ord wrote:It would have been interesting to see what happens to the torque had they used manual mode and left it locked in 7th as it pulled down to 1800 rpm. It’s possible, even likely, that peak torque is achieved by 1800 rpm and the torque curve is flat from 1800 to 2000 or 2100 rpm.
It’s interesting that 420 peak rear wheel HP is obtained at 2800 rpm which is about 89% of the engine’s rated hp. (Indicating an 89% driveline efficiency) At 2150 rpm the truck is putting down 899 lbft of torque. If you use the same drive line efficiency of 89% the crankshaft torque would be 1010 lbft of torque at 2150 rpm. The engine is only rated to put out a peak torque of 975 lbft and that is at 1800 rpm. Doesn't TQ get multiplied by the gears?
It does. The dyno numbers are derived from the rear wheel hp and represent crankshaft torque less driveline loss. For instance if the dyno rollers are spinning 1800 rpm when the engine is at 2800 rpm the roller torque would be 1225 lbft when the dyno is indicating 420 rear wheel horsepower. The torque value of 788 lbft that Banks is talking about is based on an engine speed of 2800 rpm though. (1225 roller torque x 1800 roller rpm / 5252 = 420 hp x 5252/ 2800 engine speed = 788 lbft crankshaft torque)
2022 F350 SRW Platinum short box 4x4.
B&W Companion
2008 Citation Platinum XL 34.5
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FishOnOne
The Great State of Texas
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Joined: 02/12/2011
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Well looks like the 2024 Duramax yielded 18mpg on winter blend diesel. Probably would yield 19mpg in my neck of the woods on summer blend diesel. Assuming there was no regen during this MPG test.
Link
'12 Ford Super Duty FX4 ELD CC 6.7 PSD 400HP 800ft/lbs "270k Miles"
'16 Sprinter 319MKS "Wide Body"
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FishOnOne
The Great State of Texas
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Huntindog wrote:FishOnOne wrote:Impressive... Next would like to see if there's been a fuel economy improvement. Now you are being funny. More power,towing and better economy do not go together.
Speed costs money.
How fast do you want to go?
Not talking about speed. The '20 Power Stroke received a impressive bump in HP and Torque while improving fuel economy. We also seen dyno tests that demonstrated the advertised HP/Torque were understated from the factory.
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Huntindog
Phoenix AZ
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Joined: 04/08/2002
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FishOnOne wrote:Huntindog wrote:FishOnOne wrote:Impressive... Next would like to see if there's been a fuel economy improvement. Now you are being funny. More power,towing and better economy do not go together.
Speed costs money.
How fast do you want to go?
Not talking about speed. The '20 Power Stroke received a impressive bump in HP and Torque while improving fuel economy. We also seen dyno tests that demonstrated the advertised HP/Torque were understated from the factory. I do not remember seeing a milage figure on any of my trucks stickers
Huntindog
100% boondocking
2021 Grand Design Momentum 398M
2 bathrooms, no waiting
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2020 Silverado HighCountry CC DA 4X4 DRW
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valhalla360
No paticular place.
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Joined: 08/19/2009
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Huntindog wrote:FishOnOne wrote:Impressive... Next would like to see if there's been a fuel economy improvement. Now you are being funny. More power,towing and better economy do not go together.
Speed costs money.
How fast do you want to go?
Pulling the same trailer at the same speeds on similar routes...you sure can see better efficiency.
You are presuming that if you buy a more powerful truck, you will go faster. Go faster with the old less powerful motor and you will see a drop in efficiency.
Pretty much no one tows with their foot to the floor running at absolute max output, so it's silly to assume people would suddenly do so.
Tammy & Mike
Ford F250 V10
2021 Gray Wolf
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