NW verstellen / Platzende PDEs nach Tuning | Posts 32+

hame22 wrote:

Could the NW possibly be incorrectly set from the factory, or "This was only Ulf's perspective, because the engines only started to produce significant power from 3500 RPM." wirken?

That's precisely where opinions differ.
If you have two identical engines with different low-end torque settings, and one revs up more aggressively from the top than the other, which setting is the correct one?

Does it matter for the answer "true or false" which default network setting was used, as long as it followed the manufacturer's specifications?

For each answer, there is a justification.

Hi,

Does the so-called "correction" work for you?
Did it bring about an improvement?

hame22 wrote:

Hi, Does the so-called "correction" work for you? Did it bring about an improvement?

Yes, see "perceived diagram" in the user manual.

By the way, the PD software can provide certain indications about the effect of the nozzle adjustment: specifically, that depending on the area of the nozzle opening where the PDE is located, different flow rates (mg/rotation angle) are actually achieved.

In other words, the further back on the injection cam the injection occurs, the higher the actual delivery rate will be.

Following (a bit complicated to understand):
If you advance the timing of the Northwest (NW) sensor, it shifts all the injection events on the fuel cam backwards, and the higher fuel delivery rate results in slightly higher injection volumes, which the Engine Control Unit (ECU) (presumably) doesn't detect.

Since my fuel consumption reading is quite accurate and matches the fuel consumption during overnight charging, I apparently haven't significantly altered my "all-settings" pump calibration by adjusting the nominal voltage (NW), because if I had, my overnight charging fuel consumption would be significantly higher than the average calculated by the vehicle's onboard computer (MFA).

Here's the translation:

'However, the ultra-long-stroke '2V' engine concept for the 1.9-liter engine...'
Brute force in the lower range and a certain resilience in the upper range are beneficial.

Furthermore, the influence of the necessary force that the PD elements absorb via the cam and, consequently, from the entire system, may potentially have a more negative effect at the top.

The AFN engine was subjectively more enjoyable to drive because the VP engine follows a different concept and has a more linear torque curve. For example, the AFN produces 110 horsepower at 4250 rpm and 235 Nm of torque somewhere around 1900 rpm, while the AJM produces 115 horsepower at 4000 rpm and 315 Nm of torque somewhere around 1900 rpm. It just has to feel different.

For city drivers, those who prioritize fuel efficiency, and those who want a long-stroke engine, there's nothing better than a long-stroke PD (piston displacement) engine. People who prefer a sportier feel tend to opt for a shorter-stroke CR (compression ratio) system. Regardless of the possibilities of mechanical or digital influence.

VG
Above.

Hi,

Quote:

The AFN engine was subjectively more enjoyable to drive because the VP engine follows a different concept and has a more linear torque curve. For example, the AFN produces 110 horsepower at 4250 rpm and 235 Nm of torque somewhere around 1900 rpm, while the AJM produces 115 horsepower at 4000 rpm and 315 Nm of torque somewhere around 1900 rpm. It just has to feel different.

However, I believe that's only half the truth. The ASV engine, as the successor to the AFN, also produces its 110 horsepower at 4000 revolutions per minute. I've never driven an AFN, but the ASV engine isn't exactly known for being very responsive when it comes to revving. When accelerating hard in second or third gear, you quickly reach 4700 RPM, where the engine starts to sound slightly strained... and even on the highway, it easily revs well above 4000 RPM.

Best regards,

Jan.

Good morning, everyone.

@Ulf

Quote:

yes, see "perceived diagram" in the FA.

Okay, I'm assuming there are no tests, then?
So, either a test bench or a direct current resistance.


Question for other PD drivers.
What about this one? Has anyone done that before?
with the camshaft?

Regards,
I'm sorry, I can't translate that word because it's not a complete sentence or phrase. It's just a single word.

hame22 wrote:

Then I'm assuming there are no tests, or? So, test bench or DZR.

DZR tests are available, but I am not currently aware of any dynamometer runs.

@Jan,

It's likely half the truth, but the focus shouldn't be on the RPM at rated power (those 250 RPM are irrelevant), but rather on the difference between the maximum torque and the torque at rated power. When the AJM engine around the year 2000 delivers a torque of 315 Nm and then, according to the mathematical calculations, the torque drops sharply to the nominal value, it creates a different experience compared to an older VP engine that only has 235 Nm of torque.

ObenbeiMutti wrote:

If, with the AJM around the year 2000, the bull with 315 Nm of torque "horns" you, and then, according to the mathematics, the torque drops sharply to the nominal value...

Yes, 310 Nm (315 Nm doesn't seem to be a standard VAG PD catalog value, as far as I know) at 2000 rpm corresponds to roughly 65 kW, which is 76% of the maximum power output of 85 kW.

This engine (IIRC, its name is ATJ?) is therefore already relatively close to a "constant power" machine: as long as the engine speed remains between 2000 and 4000 rpm, the acceleration at full throttle is always the same, regardless of the gear .

This particular tendency is hardly pronounced in the AFN or ASV engines: in a direct comparison, they feel much more like powerful gasoline engines, where downshifting is rewarded with significantly more power.

As long as the engine speed remains between 2000 and 4000 rpm, the acceleration at full throttle is always the same, regardless of the gear.


I don't want to leave it like that, even though I lack the physics knowledge and background information.

When I was given the first BMW (150 hp 2.0L CR), I was surprised by how lifeless it felt at low RPMs (up to 2000 RPM) and how powerful it became at higher RPMs (up to around 4300 RPM).

So, back then, I was used to seeing ARL engine data, and I overlaid the torque/power diagrams of the two engines to understand the differences. And indeed, the BMW engine doesn't reach its maximum torque of 330 Nm until 2000 rpm. However, that maximum torque remains constant all the way up to exactly 3000 rpm. Only then does the curve gently drop towards 4000 RPM, until it intersects with the curve of the Arl.

The ARL had already reached its maximum torque of 320 Nm (a single peak, not a plateau) well before 2000 rpm, but then it started to decrease immediately, and dropped significantly above 2500 rpm. (According to my recollection, it only produced around 290 Nm at 3000 rpm).

So, if you were to add up the area under each respective torque curve, the BMW would reveal its advantage starting in 2000, while the ARL had already reached its peak before 2000. And that's exactly how it feels!

From 4000 RPM, VAG cuts power (due to the ship diesel compromise, PD?), using a map-based strategy, while BMW allows the torque curve to continue normally.

Therefore, I will initially relate the perceived acceleration only to the actual torque, independent of the power, which is related to the speed (RPM). But of course, I'm happy to be convinced that my considerations are flawed .

ObenbeiMutti wrote:

Quote: As long as the engine speed remains between 2000 and 4000 rpm, the acceleration at full throttle is always the same, regardless of the gear. Therefore, I will initially relate the perceived acceleration only to the actual torque, independent of the power, which is related to the speed (RPM). But of course, I am happy to be convinced that my considerations are flawed

.
Hi,

Acceleration is achieved through power, not just torque (otherwise, the TDI's acceleration would decrease when downshifting, because it loses torque at higher RPMs ).

My quote doesn't refer to real TDI engines, but to a genuine constant-power engine.
For example, it should have the following specifications: 425 Nm of torque at 1900 rpm, and a maximum power output of 85 kW, with a consistently decreasing torque curve in between.

I had suspected something similar.

While I experience less torque at the shaft at high RPMs, the shaft spins much faster, so the reduced torque can be 'effectively compensated for by the high RPMs.'

What makes me suspicious is, for example, the electric motor. It would be a constant-torque motor, which provides a consistent force (in G-units) throughout its operation because it has a defined torque from 0 to maximum RPM, even though the power is constantly increasing.

Furthermore, I would like to incorporate my experiences with the AAZ engine into the discussion. In my case, it was actually the case that constantly shifting between 4th and 5th gear on the highway didn't achieve anything (and the same was somewhat true for the ARL).

(otherwise, the TDI's pulling power would decrease when downshifting, because it loses torque at higher RPMs).

Perhaps he would do that too, considering that you're only regaining access because of the cheaper translation.

I don't have a G-meter, and I don't have K-Power either! But you used to have those great comparison videos, in collaboration with a user named Ernst, where you benchmarked similarly heavy and motorized gasoline engines against diesel engines of the same model.

No way! According to my understanding, a motor with an ARL (Airflow Resistance Load) that delivers 270 Nm of torque at both 1500 and 3900 RPM should, during acceleration, produce the exact same G-force value in each case.

According to your thinking, it should perform better at 3900 RPM.

I'm just saying, as I mentioned, I'm questioning it based solely on my assumption, without any background knowledge of physics!

ObenbeiMutti wrote:

No! According to my understanding, a motor with an ARL (Airflow Resistance Load) that delivers 270 Nm of torque at both 1500 and 3900 RPM should, during acceleration, produce the exact same G-force value in each case. According to your thinking, it should perform better at 3900 RPM.

To resolve this apparent contradiction, one must consider the energy associated with acceleration.
W = 0.5 * m * v²
-> Accelerating from a standstill requires more energy than accelerating from a slower speed.
This extra power is provided by the engine, as its output is higher due to a higher rotational speed.

As a result, a vehicle with an ARL (presumably referring to an engine control system) accelerates equally strongly at 1500 and 3900 rpm (in the same gear!), assuming there are no speed-dependent resistances.

However, if you downshift so that the engine suddenly jumps from 1500 rpm to 3900 rpm, the increased power will pull the car forward more forcefully, even at a lower speed, despite the same torque.

Well, of course, power and torque are causally related, but what we notice is just more torque at the drive wheel when downshifting, due to the more favorable gearing, unless it's an AAZ engine.

I'm afraid it's even worse than that:

'The user Herwigw is explaining what acceleration actually is.'

To the best of my knowledge, there is a slightly more suitable metric that mechanical engineers in this context prefer to use instead of torque: the tensile force margin.

I can't provide formulas, but as far as I understand, the argument against using 'torque' as a measure of acceleration perception is that the moving masses of the motor also create a 'dynamic resistance' against a change in rotational speed. Therefore, a motor with twice the rotational inertia of another will accelerate less well at the same torque.

This would also have an impact because diesel engines require more robust connecting rods, crankshafts, etc. due to the higher combustion pressures, which further complicates the comparison between gasoline and diesel engines.


'It would essentially be saying something worse than the actual measure of acceleration, which is force.'

You yourself are writing:

Therefore, a vehicle with an ARL (Automatic Ride Height) system accelerates equally strongly at 1500 and 3900 rpm (in the same gear!), assuming there are no speed-dependent resistances.


You're absolutely right! The work done, which is related to acceleration through force multiplied by distance, is indeed the key. However, for measuring acceleration, we're only interested in the force component acting on the drive wheel. Of course, it needs to be backed up by performance, but we don't have to worry about that; our transmission takes care of it.

The only thing that's a bit of a 'back-of-the-envelope' calculation: When do I have more power at the drive wheel – in 4th gear at 2000 RPM, or in 3rd gear at 3000 RPM? That's what I'm wondering, anyway...

completely ignorant and stubborn

text
Returns the plausible value for G-force measured by the sensor.

ObenbeiMutti wrote:

it's just a theoretical calculation: When do I have more power at the drive wheel: in 4th gear at 2000 RPM, or in 3rd gear at 3000 RPM, I mean... it should return a plausible value in terms of G-force

Without considering any frictional resistance, the statement is generally correct and does not contradict my other answers.

Hi Ulf,

These tests are yours. Can you give me some numbers?
posten?