Ecodiesel power derating as temps rise?

[foo.c]

Torque is only the capacity to do work, you need to look at the rate at which it is being done (power). In the real world, you need to apply that torque over a distance to actually accomplish something.

Also, many dynos don't measure torque, they measure horsepower and then calculate the torque from the horsepower and rpm. You can do this because the relationship between the two never changes, regardless of what gearing your vehicle has.

You didn't answer my question.

After you answer the question you can compute the power yourself using the formulas that explain the relationship, which I think we both know.

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[CrazyCooter]

What evidence are you expecting? I don't have an engine dyno, which incidentally works by putting a load on the engine and measuring the torque against it.

What do you think it would show if we put a transmission between the engine and the "brake". I bet it would show more torque in low gear, the exact amount of torque in the 1:1 gear and less torque in overdrive. Can we at least agree on that?

I can answer that for you ....... Yes, the lower transmission gear will multiply torque the crankshaft is putting out. Again, we've already established she will pull all day at 10mph! HP is what will allow us to travel up the hills at a safe speed.......

H = T x rpm/5252

 

[ShadowsPapa]

I can answer that for you ....... Yes, the lower transmission gear will multiply torque the crankshaft is putting out. Again, we've already established she will pull all day at 10mph! HP is what will allow us to travel up the hills at a safe speed.......

H = T x rpm/5252

You need to change your name to not-so-crazy........

 

[CrazyCooter]

You need to change your name to not-so-crazy........

The "Crazy" part came from the way I operated motorized equipment and "Cooter" from me being a mechanic like Cooter on Dukes of Hazzard. I'm not so crazt anyomore since it takes longer to heal up!

 

[RobertRinAustin]

No background in diesels, but lots of experience tuning turbo engines back in the day. All the engines I tuned had a timing reduction feature based on intake air temps (IAT). Hit the threshold and you drop 5 degrees of timing across the board which cut power and hopefully IATs. Some had a second threshold that would trigger further reductions.

 

[foo.c]

I can answer that for you ....... Yes, the lower transmission gear will multiply torque the crankshaft is putting out. Again, we've already established she will pull all day at 10mph! HP is what will allow us to travel up the hills at a safe speed.......

H = T x rpm/5252

We're finally getting somewhere.

So is there more HP or whatever unit we want to use to get up the hill in 8th gear or 5th gear, assuming we can reach the same wheel speed in both gears? (Does it even hold 8th?)

To be totally honest, for all I know no matter what gear you are in it will be in boost, but I know in general the lower the load on the engine the lower the boost is, and you accomplish that with lower gears in the trans or higher (numerically) in the diff.

 

[CrazyCooter]

We're finally getting somewhere.

So is there more HP or whatever unit we want to use to get up the hill in 8th gear or 5th gear, assuming we can reach the same wheel speed in both gears? (Does it even hold 8th?)

To be totally honest, for all I know no matter what gear you are in it will be in boost, but I know in general the lower the load on the engine the lower the boost is, and you accomplish that with lower gears in the trans or higher (numerically) in the diff.

Most of us have already been there.....Are you getting it now?

Same HP in any available gear except for any possible detuning the factory may have done to save the drivetrain. It all depends on engine RPM and torque available at that particular RPM as the formula I posted above will tell you. With the 8 speed gears being so close together, we have the ablity to keep the engine at peak as needed.

 

[foo.c]

Most of us have already been there.....Are you getting it now?

Same HP in any available gear except for any possible detuning the factory may have done to save the drivetrain. It all depends on engine RPM and torque available at that particular RPM as the formula I posted above will tell you. With the 8 speed gears being so close together, we have the ablity to keep the engine at peak as needed.

Darn, we were making progress.

I'll leave you to it.

 

[CrazyCooter]

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.

 

[Gruffid]

I hate to ask this, because it seems like it’s very simple. And yes, I have read every post, but this thread has been alive for awhile and I can’t remember if it’s been addressed yet or not…

Have we checked our air filters? Knowing that our EDs are very high strung and are already operating at high temps, it seems like those of us in hot environments have more de-rating. Many of these hot environments also have a lot of dust or dirt in the air. Depending on where you live, maybe also ash from wild fires.

I’m not not saying it’s the answer to all our prayers, but it might be a contributing factor.

 

[CrazyCooter]

I hate to ask this, because it seems like it’s very simple. And yes, I have read every post, but this thread has been alive for awhile and I can’t remember if it’s been addressed yet or not…

Have we checked our air filters? Knowing that our EDs are very high strung and are already operating at high temps, it seems like those of us in hot environments have more de-rating. Many of these hot environments also have a lot of dust or dirt in the air. Depending on where you live, maybe also ash from wild fires.

I’m not not saying it’s the answer to all our prayers, but it might be a contributing factor.

I did not pull my airbox lid like I would for a client since I know the history of my vehicle. Maybe I should just in case.......

 

[WXman]

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.

 

[CrazyCooter]

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.

Within this thread or one of the others about high oil temps, there was discussion about the what it was doing to the oil so I thought the UOA was relevant.

My thread, my rules. You can show yourself to the door if you don't like the discussion here.

 

[houseofdiesel]

Torque is only the capacity to do work, you need to look at the rate at which it is being done (power). In the real world, you need to apply that torque over a distance to actually accomplish something.

Also, many dynos don't measure torque, they measure horsepower and then calculate the torque from the horsepower and rpm. You can do this because the relationship between the two never changes, regardless of what gearing your vehicle has.

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.

 

[ShadowsPapa]

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.

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I can get us some of our famous deer meat to go with the popcorn - deer jerky and a few locally made brews.

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