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Ecodiesel power derating as temps rise?

ShadowsPapa

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Torque is the amount of force being applied. HP is the amount of work getting done. Capacity is not the right word. Hence why toque ratings for bolts is the maximum amount of force applied as to not stretch, strip, or stress a bolt or part. Torque is needed to move dead weight and overcome the laws of physics against gravity. As that dead weight loses the resistance of its weight (on flat ground), you do not need as much torque to move it. Which is where the new high rev Euro diesel shines. As you hit a grade gravity increases and begins to add resistance. Torque once again is needed to maintain speed. The torque/horsepower curve of these Euro high rev diesels go past the peak of the torque curve and falls off after 3000-3200 rpm as HP climbs and surpasses it. When hauling on a grade I'd avoid running over 3200 rpm, as you will not have the torque necessary to increase or maintain speed.

So even the basic definition of HP being a measure of the work getting done is misleading since it only applies on flat ground with the least amount of load/resistance applied. Hence why people always lie about their dyno numbers and add corrections.

Full-load curves_OEM vs Hot vs Eco.png
HP is originally defined as LIFTING dead weight straight up. Horses pulling hay up into the barn, etc.
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CrazyCooter

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HP is originally defined as LIFTING dead weight straight up. Horses pulling hay up into the barn, etc.
So all of this tech talk and math calculations are irrelevant since we aren't farming with our Gladiators? ;)
 

WXman

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A better way to look at it is: torque is how much work the engine can do, and horsepower is how fast it can do that work.

Gladiator makes a perfect example of this because the P-star engine will outrun the EcoD in a drag race, but the EcoD will tow in higher gears with the cruise control set to the same speed as the P-star.

A truly powerful engine will have gobs of both. But often it's a trade-off, and ability to do work is more important than speed of doing work in a pickup truck, so torque wins.
 

rharr

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My uoa came back and looks normal for a relatively new engine.

I changed the oil when the dash told me to which came out at 6900 miles, but wouldn't hesitate to go 10k+ with this oil. TBN and viscosity are still up there. Iron, copper, and silicon ever so slightly elevated but expect those to drop with full break in. Fuel dilution and soot are much lower than I expected.

I uploaded the file for those interested.
Tony,
FYI this is the interwebs, and your report contains personal information now shared on the internet. Might want to do some PDF redacting.

Nice Shop btw, looks like you do some interesting fab work. Like the King laydown setup.
 

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CrazyCooter

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Tony,
FYI this is the interwebs, and your report contains personal information now shared on the internet. Might want to do some PDF redacting.
I appreciate your concern.

It's my work address and info which is public knowledge for anyone who looks for it...... One time I had a parts manufacturer on here stalk me with just hat you see in my profile......first name, location, and that I was in the business.

It's also a game of ours to locate You Tuber's houses on what little info they give in the video.....You wouldn't believe how scary easy it is. Hopefully weirdos aren't that resourceful?
 

ShadowsPapa

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That reminds me - why I take motortrend, Car and Driver and some others with a grain of salt - C&D is the same rag that says it takes a NASCAR pit crew and a gable hoist to remove the Jeep roof.......and the Bronco roof is SOOO much easier. The guy must have had chills going up his leg over the Bronco....... they ain't what they used to be.

All images show horses LIFTING, but historians say it was due to the ponies used in mines to haul coal carts - and since he was aiming to sell his improved engine to mine owners, he used ponies as an example and extrapolated what a larger hose could do.

https://www.drive.com.au/news/the-o...y-behind-the-term-rev-heads-take-for-granted/
Watt had been working with ponies at a coal mine and had established that an average animal could move 220 pounds of coal (100kg), along a 100-foot mineshaft (30m) in one minute, all day long

https://www.thoughtco.com/where-did-the-term-horsepower-come-from-4153171

Whatever, it's not a very scientific comparison as he originally used ponies.....and he assumed the task was being done by fresh ones at that, not what they could sustain for an hour.

Anyway, the real history on it was some fun research and reading.

It's also a game of ours to locate You Tuber's houses on what little info they give in the video.....You wouldn't believe how scary easy it is. Hopefully weirdos aren't that resourceful?
You mean like showing mail boxes, the front of the house, types of trees, etc. and with the time of day, angle of the sun and now Google street view stuff.......
 

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Matches the experience I saw from a guy in Arizona the other day. He said the weather has been torrid out there lately, and even driving up into higher elevations he has zero issues.

I'm starting to wonder why some of us never have issues and others claim they do. What's up with that? Heck I even have a 12k winch mounted right in front of my grille and I still never overheat even on the hottest days.

Different engine tune for a different region, one with higher altitudes? I had issues going from Oregon to Utah/Colorado... Biggest problem was on the 80mph hill climbs in Idaho... not towing, just the fam, and the gear for a trip to Moab.

I just can't believe that some folks are doing similar trips with no problems... I drive like my grandpa, unless the speed limit sign says 80, then I want to go the speed limit... but not on a hot day, the diesel says NOPE... My Father in Law derated at the same spots I did in his JL Rubi Diesel too... I want to know what is different between the ones that are not seeing the problem, and mine, and my F-i-L's JL too!
 
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CrazyCooter

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You mean like showing mail boxes, the front of the house, types of trees, etc. and with the time of day, angle of the sun and now Google street view stuff.......
Yep, then drone footage combined with that they almost always recently to a small community, so fewer buildings to look for. My wife has a job that sometimes requires her to scan sat images, so she is semi pro at this kind of thing.....
 

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So we went from "why does my engine derate when I abuse it at 2 miles above sea level?" to a classroom discussion on horsepower vs torque, to an oil analysis of Amsoil branded oil being analyzed by a company owned by Amsoil (I mean, really? What did you expect them to say?) and now we're moving on to air filters which have no ability to alter IATs.

Whew... hang on for the ride boys and girls. :CWL:
so we went from “let’s have an open discussion on a topic that seems to affect several of us” to “let’s abuse, insult and troll anyone who isn’t as smart as I am”.

wow. I bet you’re loads of fun to be around. How about if you don’t have anything productive to contribute, keep you’re trollful comments to yourself?
 

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houseofdiesel

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That reminds me - why I take motortrend, Car and Driver and some others with a grain of salt - C&D is the same rag that says it takes a NASCAR pit crew and a gable hoist to remove the Jeep roof.......and the Bronco roof is SOOO much easier. The guy must have had chills going up his leg over the Bronco....... they ain't what they used to be.

All images show horses LIFTING, but historians say it was due to the ponies used in mines to haul coal carts - and since he was aiming to sell his improved engine to mine owners, he used ponies as an example and extrapolated what a larger hose could do.

https://www.drive.com.au/news/the-o...y-behind-the-term-rev-heads-take-for-granted/
Watt had been working with ponies at a coal mine and had established that an average animal could move 220 pounds of coal (100kg), along a 100-foot mineshaft (30m) in one minute, all day long

https://www.thoughtco.com/where-did-the-term-horsepower-come-from-4153171

Whatever, it's not a very scientific comparison as he originally used ponies.....and he assumed the task was being done by fresh ones at that, not what they could sustain for an hour.

Anyway, the real history on it was some fun research and reading.



You mean like showing mail boxes, the front of the house, types of trees, etc. and with the time of day, angle of the sun and now Google street view stuff.......

Totally agree since it doesn't factor in how many less revolutions a diesel takes to create the force and energy that it creates compared to a gas mill that is turning twice as often to create that same energy and force.
 

ShadowsPapa

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Totally agree since it doesn't factor in how many less revolutions a diesel takes to create the force and energy that it creates compared to a gas mill that is turning twice as often to create that same energy and force.
I used to own both gas and diesel tractors. I had what at the time was the biggest two wheel drive tractor Case made. A neighbor was showing off his new JD 4x4 - a big 4 wheel drive John Deere with a massive engine.
He bought a big chisel plow to go with it. We were drinking and joking around one evening and he was going on about his new tractor and I laughed and said "my Case will pull that chisel across your field without blinking an eye" and made a bet. OOPS, alcohol talking there - oops. Well, I had to go with it. So he made it even tougher - he was to pull that plow half-way through his field, leave it in the ground, unhitch, and I was to back my Case up and hook on and pull it from right where he left it - same depth and all. (and he had it set pretty deep)
Time to make good or pay up.
I hooked up, put it in one of the lower gears, wound it up tight and let the clutch out. Shudder, jerk, black coal out the stack............ and she started moving. The RPM was WAY down there, any gasser would have died instantly, but that diesel kept gaining and gaining RPM and I made it across. Not real fast, but it was a great example of how low can you go in RPM and still have massive torque to get that load moving from a dead stop a good foot or more in the ground.
And I LOVED the sound of those Case diesels, loved that low exhaust note. So SMOOTH, I could listen to it all day - oh, wait, I usually did.
 

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I had a similar situation with my JTRD on the way back from Boise. The computer said I needed a regen, but the filter was only 29% full. It still derated and went into limp mode with dash saying there was an exhaust problem and to take it to the dealer. The next 3 hours I was going between 45 and 75 mph depending on the incline or decline.
What was the fix? A force regen?
 
 







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