4x4ord
Alberta
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Joined: 12/23/2010
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Huntindog wrote:4x4ord wrote:travelnutz wrote:Me Again,
DUH! HP is merely a theoretical calculation moniker derived from how fast the TORQUE applied to the drive wheels rotates them thus creating measurable RPM. HP is NOT a direct measurable value! Zero torque = Zero RPM and thus Zero HP could even be calculated. Even 1000 lbs feet torque with zero RPM = zero HP. There is Zero RPM if there's insufficient TORQUE to rotate the wheels. HP is merely a theoretical value calculation, not a measured value!
A "horse" does not have a given pulling or rotational strength value as there are vast differences is sizes and pulling strengths of all the various horses. A given size horse's pulling strength can be actually measured but which horse?
The more FORCE (TORQUE) one applies to wheel shaft, the more RPM's it will turn! No where is the word HP used or even involved to make the wheel turn to any RPM's!
TORQUE and RPM are measurable but NOT HP as it's only a theoretical calculation!
Read the article that meagain posted a link to. Power is the rate of doing work. Neither Rpm nor torque are needed to calculate HP. The formula: HP= torque x rpm/5252 is derived from the definition of horsepower(1 horsepower is the power required to lift 550 lbs 1ft in 1 second). If the formula involving rpm and torque were to be stated accurately it would read HP = torque x rpm x pi/16500. No matter. It is a well known fact that 4.10 gears will perform better in towing than 3.73s
So obviously, if the DA had 4.10s it would do better.
At one time, the Ram/Cummins was available with 3 different gear ratios, and 3 different tow ratings.
I will leave it up to the math gurus to debate as to why that is.
On this particular hill the Chevy might have been geared right. It started out at 55 mph and averaged about 46 mph so it likely spent a fair amount of time at around 40 mph. With 235/80r17 tires and the 3.73 gears the Duramax would be running 2854 rpm at 40 mph in second gear. If it had had a 4.10 final gear ratio at 40 mph the engine would be turning 2427 rpm in 3rd gear or 3137 in 2nd gear.....In either gear the truck would have slowed down.
Edit: The Ford should have been pretty comfortable at 40 mph with 4.10 final drives. It would have been running in 3rd gear at 2662 Which is pretty close to peak HP.
* This post was
edited 03/04/17 05:22am by 4x4ord *
2023 F350 SRW Platinum short box 4x4.
B&W Companion
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Wild Card
North Carolina
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Joined: 10/13/2016
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4x4ord wrote:travelnutz wrote:Me Again,
DUH! HP is merely a theoretical calculation moniker derived from how fast the TORQUE applied to the drive wheels rotates them thus creating measurable RPM. HP is NOT a direct measurable value! Zero torque = Zero RPM and thus Zero HP could even be calculated. Even 1000 lbs feet torque with zero RPM = zero HP. There is Zero RPM if there's insufficient TORQUE to rotate the wheels. HP is merely a theoretical value calculation, not a measured value!
A "horse" does not have a given pulling or rotational strength value as there are vast differences is sizes and pulling strengths of all the various horses. A given size horse's pulling strength can be actually measured but which horse?
The more FORCE (TORQUE) one applies to wheel shaft, the more RPM's it will turn! No where is the word HP used or even involved to make the wheel turn to any RPM's!
TORQUE and RPM are measurable but NOT HP as it's only a theoretical calculation!
Read the article that meagain posted a link to. Power is the rate of doing work. Neither Rpm nor torque are needed to calculate HP. The formula: HP= torque x rpm/5252 is derived from the definition of horsepower(1 horsepower is the power required to lift 550 lbs 1ft in 1 second). If the formula involving rpm and torque were to be stated accurately it would read HP = torque x rpm x pi/16500.
Yep, HP is a fictional number. Torque does the work
2015 Ram 3500 Dually
Sundowner 2286GM Pro-Grade Toyhauler
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4x4ord
Alberta
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Joined: 12/23/2010
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Wild Card wrote:4x4ord wrote:travelnutz wrote:Me Again,
DUH! HP is merely a theoretical calculation moniker derived from how fast the TORQUE applied to the drive wheels rotates them thus creating measurable RPM. HP is NOT a direct measurable value! Zero torque = Zero RPM and thus Zero HP could even be calculated. Even 1000 lbs feet torque with zero RPM = zero HP. There is Zero RPM if there's insufficient TORQUE to rotate the wheels. HP is merely a theoretical value calculation, not a measured value!
A "horse" does not have a given pulling or rotational strength value as there are vast differences is sizes and pulling strengths of all the various horses. A given size horse's pulling strength can be actually measured but which horse?
The more FORCE (TORQUE) one applies to wheel shaft, the more RPM's it will turn! No where is the word HP used or even involved to make the wheel turn to any RPM's!
TORQUE and RPM are measurable but NOT HP as it's only a theoretical calculation!
Read the article that meagain posted a link to. Power is the rate of doing work. Neither Rpm nor torque are needed to calculate HP. The formula: HP= torque x rpm/5252 is derived from the definition of horsepower(1 horsepower is the power required to lift 550 lbs 1ft in 1 second). If the formula involving rpm and torque were to be stated accurately it would read HP = torque x rpm x pi/16500.
Yep, HP is a fictional number. Torque does the work
If you read the article that meagain has posted the link to and come up with the conclusion that "HP is a fictional number. Torque does the work." There maybe no hope for you.
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ib516
Canada
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Joined: 04/18/2003
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4x4ord wrote:It looks like they need to run the new 445 HP/ 915 lbft Duramax up against the old 397 HP/765 lbft engine.
click
They mention that run in the video and state it was 1400# less than this current load. This load, the trailer alone was 22800#, and they don't mention people/cargo weight. Environmental conditions can have a slight effect too (wind)?
Prev: 2010 Cougar 322QBS (junk)
02 Dodge 2500 4x4 5.9L CTD 3.55
07 Dodge 3500 4x4 SRW Mega 5.9L CTD 3.73
14 Ram 2500 4x4 Crew 6.4L Hemi 4.10
06 Chevy 1500 4x4 E-Cab 3.73 5.3L
07 Dodge 1500 5.7L Hemi 3.55 / 2010 Jayco 17z
All above are sold, no longer own an RV
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ib516
Canada
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Joined: 04/18/2003
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Bionic Man wrote:IdaD wrote:I haven't watched the video but were these guys running at wide open throttle or were they holding back to stay within the speed limit? If the latter is the case this is meaningless. If the former is the case this is still meaningless because the fastest one is only 15 seconds quicker than the slowest one. Power isn't really a distinguishing quality with these newer diesel trucks and that's been the case for awhile.
I haven't watched the video yet either, but I am pretty sure that it takes 8 minutes to run up at the 60 MPH speed limit.
None of the trucks can maintain the speed limit with the load. I think they mention that the Ford couldn't exceed 40 or 45 mph. I'd have to watch it again to be sure. In any case, it is a test of the power trains.
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GeoBoy
Bennington
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IdaD wrote:I haven't watched the video but were these guys running at wide open throttle or were they holding back to stay within the speed limit? If the latter is the case this is meaningless. If the former is the case this is still meaningless because the fastest one is only 15 seconds quicker than the slowest one. Power isn't really a distinguishing quality with these newer diesel trucks and that's been the case for awhile.
Bingo! Buy what you like, they are all very capable.
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4x4ord
Alberta
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4x4ord
Alberta
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ib516 wrote:4x4ord wrote:It looks like they need to run the new 445 HP/ 915 lbft Duramax up against the old 397 HP/765 lbft engine.
click
They mention that run in the video and state it was 1400# less than this current load. This load, the trailer alone was 22800#, and they don't mention people/cargo weight. Environmental conditions can have a slight effect too (wind)?
Look at it this way:
The old Duramax with 397 HP and 765 lbft of torque was able to lift 29650 lbs 2100 ft in 588 seconds. If you do the math: 29650x2100/(588x550) you find it did work requiring 192.5 HP plus whatever it took to overcome air and Roling resistance....Likely another 80 HP or so.
The 2017 Duramax lifted 31750 lbs 2100 ft in 615 seconds. Multiple that out and you find it put 197 HP to the pavement plus the 78 or so HP required to overcome drag and rolling resistance.
I'm not seeing the additional 48 HP and 150 lbft of torque that Chevy is claiming.
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4x4ord
Alberta
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I wonder if the trucks performance is based on the manufacturers advertising budget? Why would the Ford pull a 30,000 lb trailer up the hill a minute faster than the Ram and now with a lighter trailer it can't keep up? Why can't the new Duramax blow the doors off the old one?
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ib516
Canada
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Lots of questions for sure.
Like I said, I think the take away is that they are all so close it doesn't matter much, notwithstanding the advertised tow rating or hp/tq differences.
Buy the one you like from the dealer you think will look after you.
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