LD-Regelung ALH | Posts 16+

Jochen_145 wrote:

This also confirms my assertion that the load on the charger is dependent on the volumetric flow rate, and therefore, overshoots in low speed ranges are perfectly acceptable. Unfortunately, this also means that you and Rainer have invested a lot of work, which is partially useless. Okay, but the synchronization of the VSKF at high speeds remains an important point that must not be forgotten. Therefore, your work is not entirely in vain.

Hi Jochen,

At low engine speeds (regardless of where the transition range lies), the turbocharger might be operating with less boost, but the head gasket is still subjected to unnecessary stress at any engine speed.

In the standard configuration, there should still be sufficient strength reserves, but it's certainly not a mistake to adjust the lambda target (LDR) in tuned engines so that the lambda values do not exceed the overshoot values of the factory settings.
If the material already has to withstand higher thermal loads (even at moderate speeds, as soon as a sufficient amount of additive can be injected!), then the pressure spikes shouldn't cause twice the material stress.
That's certainly my idea of a "gentle" tuning; for that, I'm happy to accept a more comfortable LD setup, and I'll pass the waiting time by looking at the LDA, while the popometer reports the gently increasing thrust .

And once you can estimate the expected torque increase, it's no longer a problem in urgent situations to apply the accelerator earlier to compensate for the delay .

At low engine speeds (regardless of where the transition range may be), the turbocharger might be operating with less boost - but the head gasket will be unnecessarily stressed at any engine speed.

Generally correct, but you should also consider the start of injection or the start of boost, which, at e.g., 2000 rpm, is significantly closer to Top Dead Center (TDC) than at 4000 rpm. (In my Leon, it's even 8° difference).
Therefore, in this case as well, the load on the ZKD (presumably a specific component) is not quite as critical, even with a higher LD (presumably a load or performance parameter).

It only gets really bad when this happens at high RPMs. And then it affects both the turbo and the head gasket, and I agree with you on that.

but it is certainly not a mistake to adjust the LDR in tuned engines so that the LD peaks do not exceed the overshoot of the factory settings.

Sure, if I take the Seat over-the-top as a basis .

That's certainly my idea of a 'gentle' tuning.
That's perfectly fine, it's your handwriting! However, it's subjective and therefore cannot be used as an argument for good or bad tuning. In this case, the IMA (Instantaneous Maximum Acceleration) criterion of 1 or 0 applies, which means: either it's above what the engine can achieve, or it's within its mechanical capabilities.

Best regards, Jochen.

Okay, I adjusted the VTG rod by two more rotations without any specific instructions.

The surging/hesitation is completely gone, even in the lower gears.

"Anyone who thinks that the lower load-carrying capacity (shown in the upper right corner of the attachment) would proportionally reduce the torque should take a look at the image below."
The purple indicator shows that the engine is already out of the "roughness" range in 5th gear at 1300 rpm. Thanks to the reserve of the "roughness" control, it doesn't immediately fall back into the "roughness" range if the load drops slightly below the target value (bottom image, right edge).

The slower increase in speed in the upper right corner is, incidentally, only due to a slope during the log .
(The left half of the top diagram simply repeats the data from my post on November 25th.)

The perceived "temperament" of Ibiza hasn't noticeably changed, at least according to my personal assessment.
That's why I wonder why Seat deliberately subjects the material in the production line to overpressure up to 0.3 bar.

Therefore, I wonder why Seat deliberately subjects the material in the production process to overpressure up to 0.3 bar.

Hello Ulf,
That's not really something you should be talking about at this point, especially when discussing speeds of over 1300 rpm, a rate of over 35 mg/h, and a pressure of under 1.0 bar, and referring to the deliberate mistreatment of materials.

If you believe that an excessive load is being created, first try not to attempt an overtaking maneuver at 80 or 90 km/h, or to drive the mountain roads with the Autobahn speed limit...

What do you think the handling will be like now, if you're driving with Christel's Ibi in the mountains, and the supercharger has to provide 1300hPa of boost instead of 1000hPa?

However, since you still want to have adequate responsiveness even under these circumstances, you should be aware that the charger's control system is designed to meet the needs of the average sporty Seat customer.

It would also be interesting to know what emission class (particulate matter) the AHL would achieve if it were completely integrated into the smoke reduction system .

Best regards, Jochen.

Hello Ulf,

My altitude logger has also been showing high overpressure readings (LD up to 2450 mbar) for a long time.

I also considered having the rod machined to a longer length, but I didn't do it because of the terrible installation situation.

Did you experience the camel driver effect before?
I'm also interested in the current engine characteristics. It should run more smoothly, without the 'boost effect,' compared to when it's over-revving.

Sure, here is the translation of the text from German to English:

'MFG' is an abbreviation for 'Mit freundlichen Grüßen,' which means 'Sincerely' or 'Best regards' in English.

Jochen_145 wrote:

Seriously, are you actually talking about something exceeding 35 mg/h and below 1.0 bar LD, while discussing "maltreating" materials at a speed of over 1300 rpm?

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No, I was referring to the "overshoot" (which wasn't posted as a graph here) in the standard trim. Das tollste was ich in den Ibiza-Logs habe, sind 2275 mb bei einem Soll von 1950 mb = 0,325 bar Überschwinger, bei einer Drehzahl von schlappen 3200 rpm! Dem Drehzahlanstieg nach war das im 1. oder 2. Okay. Since VAGCOM tends to underestimate or truncate the actual peak load values (due to the sampling rate or software filters) rather than exaggerate them, the actual pressure was likely even "a little bit" higher. Do you still consider something like that to be completely harmless, even with an ALH engine and the smallest 1.9-liter turbocharger?

What do you think the driving characteristics would be like now, if you were driving Christel's Ibi up into the mountains, and the turbocharger had to produce 1300hPa of boost instead of 1000hPa?

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Maybe such a trip will happen someday. After all, we also live at ~500 meters above sea level.

that the control of the charger was designed for the general sporty Seat customer.

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Sporty, well... I would only classify the ALH as sporty as long as it could move the maximum weight of an original Polo. :wink:It would also be interesting to know what emission class (particulate matter) the AHL would achieve if it were completely within the smoke reduction system.

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According to the ALH opacity, for example, approximately 760 mg of air are required to release the 37.5 mg of the torque peak. This results in a mass lambda of 1.38 -> I'm not worried about soot values yet.

Did you experience the camel driver effect before?
I would also be interested in the current engine characteristics. It should run more smoothly, without a "boost effect," than with overshoot.
I didn't notice any camelback effect or boost effects, probably because the engine hadn't yet entered the "muddiness" phase during the undershoot (after the overshoot).

As I said, I don't find the engine to be noticeably slower now.
Perhaps the power delivery from the low RPM range when accelerating at full throttle in the lower gears is now slightly more hesitant - but that could also be an illusion, because the LDA indicator is no longer moving so wildly, and its "calmness" might be subtly reflected in the "butt-o-meter" reading }.

Das tollste was ich in den Ibiza-Logs habe, sind 2275 mb bei einem Soll von 1950 mb = 0,325 bar Überschwinger, bei einer Drehzahl von schlappen 3200 rpm! Dem Drehzahlanstieg nach war das im 1. oder 2. Okay.

I can help with that.
'Ask Martin what all he measured with the Leon. These overshoots are normal for them. I also have significant overshoots: 0.25 bar is the norm with VAG-Com.'
In addition, Seat uses the 'noisy' turbochargers that were rejected by Audi and VW due to quality control issues.
Do you still consider something like that to be completely harmless, even with an ALH engine equipped with the smallest 1.9-liter turbocharger?
To be honest, yes, in the standard configuration!
I believe that at an altitude where the atmospheric pressure is 300 hPa, these oscillations can be almost completely eliminated without needing to modify the rod.
If these overspeeding situations were dangerous, Rainer would have to rethink his approach to performance improvements, because he is precisely using these extreme limits to allow the IDR to maintain a higher LD (load density) continuously, without the chargers failing.

Since the same charger is used in ASV machines, where it needs to continuously provide 2050hPa instead of 1950hPa, and it achieves this with factory approval, I think you might be being overly sensitive with this engine.
It has already been clarified that the over-pressure condition only becomes 'bad' when the upstream volume exceeds the compressor's limit.
Since this loader still delivers consistently 1800hPa LD at 4746rpm, and even at a 900hPa ambient pressure, it shows that a short overshoot of 300hPa at 3200rpm can be considered negligible.

Sporty, well... that's how I would only classify the ALH, as long as it could only move the weight of an original Polo.

Ohhh, Seat's target audience is sporty car enthusiasts within the VAG group.
Auto emoción... the Alfa from Spain... Read the brochures .
This also applies to the 1.2 gasoline engine with ?? 65 hp .

Best regards, Jochen.

Hi,

Don't worry, 2275 mbar at 3100 rpm is already sufficient for the ALH .

Best regards, Rainer.

Jochen_145 wrote:

Since the same charger is also used in ASV vehicles, where it needs to continuously provide 2050hPa instead of 1950hPa, and it achieves this with factory approval, I think you might be being a bit too sensitive about this engine.

You might be right in terms of the "absolute red lines of the material." However, minimizing pressure spikes can save...
1. unnecessary (short-term) speeds for the loader.
2. Avoid unnecessary mechanical stress on the cylinder head screws / the cylinder head gasket.

I simply assume that materials with reduced peak loads in the motor (compared to the normal OEM maximum values in the motor) have an increased expectation of durability – essentially, a bit like the "indestructible" old Mercedes-Benz WK taxi diesel engines.
As long as this increased resistance to settling is achieved without any noticeable drawbacks, why not?

Quote:

Ohhh, the target audience for Seat are sporty car enthusiasts within the VAG group. Auto emoción... the Alfa from Spain... Read the brochures . This also applies to the 1.2 gasoline engine with ?? 65 hp

.
. . . which, thanks to its "better" minimal equipment, has to lug more dead weight around compared to, for example, the bare-bones base Polo .
But I know that in the age of facades and superficiality, sportiness is no longer defined by crass data like acceleration times, but by image...

I simply assume that materials with reduced peak loads in the motor 1 (compared to the normal OEM maximum values in motor 2) have an increased expectation of durability - essentially, a bit like the 'indestructible' old Mercedes-Benz WK taxi diesel engines.
As long as this increased expectation of stability is achieved without any noticeable drawbacks -> why not?

Hello Ulf,

Okay, this approach is fundamentally easy to understand.
Does the Ibiza have an EDC15V?

Why don't you take a more radical approach?
Reduce the Lambda value to an acceptable level, adjust the LD accordingly, and shift the peak power output to a higher RPM range.

Here's how you can reduce the load on the server, the overall load on the ZDK, etc.
It's possible that there might even be a bit more torque available.
You can also eliminate these overshoots using this method.

Besides the fact that Christel shouldn't be able to fully rev the engine, you would have advantages in terms of durability and possibly even fuel consumption.

Best regards, Jochen.

Jochen_145 wrote:

Does the Ibiza have an EDC15V? Why don't you take a more radical approach? Reduce the Lambda value to an acceptable level, adjust LD accordingly, and shift the peak power to a lower RPM range.

It's likely that the 018EE is not an EDC15. In any case, I can't access the data set with my current tools, not even to read it out (the file on my computer comes from somewhere else - and it's only 256 kB in size instead of 512).

Furthermore, Christel doesn't want her engine completely overhauled – it's a "women's bazaar." Those who are familiar with that kind of thing know the chances of success when trying to compete against it are slim.

Hello Ulf,

Is the 018EE similar to the 018AE?
I found something on my hard drive related to a Golf 4 ALH.

In the description, it mentions something about Chip A and Chip B .
The file size is 2 x 128MB.
Therefore, it appears to be an MSA12.

My colleague experienced a similar issue with the MSG in his AHH Passat. In his case, it also required soldering.
The housing looks like an EDC15, but the connector is not a 121-pin connector. I also have a similar MSG unit in my company's inventory.

So, absolutely nothing to do with OBD...

Can Rudi or Rainer confirm or correct this?

'Women's flea market'. Those who know what that is, understand the chances of success if you try to compete with it.

Oh, I know that.
That's like closing a theater .

Best regards, Jochen.

@ Ulf

I just reviewed my logs.

I have a Series Soft LD overspeed protection system with a setting of 316 hPa at approximately 2250 rpm.
tuningfile 348 hPa @ ~ 2270 rpm


If the "Small" model 1749VA is already designed to handle such large overloads, then my "Large" model 1749VB must be able to withstand even more, which makes the overloads seem less problematic at such low speeds.

What kind of car does your (wife?) Cristel drive?

3 Phasen Biber wrote:

I have a Seriensoft LD overspeed protection system set to 316 hPa at approximately 2250 rpm. tuningfile 348 hPa @ ~ 2270 rpm

Um - when tuning, you can't really calculate the overshoot (LD Actual - Setpoint) because your setpoint scale ends at 2601 mbar.
More importantly, the absolute height of the pressure maxima is crucial. If you start with a tuning target of 2601 and add 348 mbar, this results in approximately 2.95 bar, which is 0.45 bar more than the standard setting .

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If the "Small" 1749VA is designed for such large overshoots, then my "Large" 1749VB must be able to handle even more, which makes the overshoots seem less problematic at such low speeds.

Don't confuse the LD setpoint ("holding pressure") with the reserves for overshoots!
Given that the VB loader is already highly optimized and operating near its performance limits for its size, its reserves for overshoot are likely to be smaller rather than larger compared to the "smaller" loaders.
Therefore, I don't consider your overpressure settings of up to 0.45 bar above the standard pressure to be safe, but definitely unnecessary. With the right knowledge, it's possible to keep these overpressure settings low even when tuning, so that the typical pressure spikes of the standard trim are not exceeded.

Quote:

What kind of car does your (wife?) Cristel drive?

An ALH-Ibiza. By the way, it doesn't have the VA turbocharger, but only the GT1749V, so it's the lowest performance level. Since the same turbocharger was also used in the ASV, it probably has the "largest possible" reserves for overboost with the ALH, but you shouldn't simply transfer those values to the turbochargers of the more powerful versions (see above).

@ Ulf

In my SW, the overhanging parts are not actually larger than in the standard software .
Is there perhaps another problem?

Do you have a performance curve for the 1749 VB?
Otherwise, it's just pure speculation!

3 Phasen Biber wrote:

In my sw, the overpressure values are not actually larger than in the standard software.

If the average standard ARL also regularly experiences overpressure up to 2.95 bar (with a setpoint of 2.50 bar) without the VTG clamp, then that would be quite significant compared to the other MCBs -> are you sure about that?

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Do you have a characteristic curve for the 1749 VB? Otherwise, it's just pure speculation!

I don't have a VB data field.
However, speculation can be made somewhat "more likely" through comparisons with similar things and corresponding deductions (as I attempted to do above).