Aiming for a standard wastegate turbo with MSG...

Another extreme crafting fundamental question :

A normal wastegate turbo can be influenced in terms of boost pressure build-up by tapping the line to the wastegate and partially releasing the pressure through a valve. The damper, a simple pneumatic component, is then commonly referred to as a "steam wheel".

If you replace the wastegate with an N75, can you use a standard wastegate turbo with a TDI-MSG (for TDI with wastegate turbochargers)?
One can simply connect the N75 so that the overpressure goes directly to the wastegate.

That would, of course, only affect the maximum boost pressure, so it would be a rather crude control. I also don't know how this system would function in a sluggish way.
But the principle is similar to a TDI-Wastegate-Turbo, except that the pressure regulator on the wastegate is missing.

Opinions?
(the question of whether one needs something like this, I'll leave that out)

Greetings
Jens

Hello Jan,

You have just described the path that is followed when controlling the charging pressure in an AHU, AHH, 1Z etc.

Do you happen to have a pressure canister at the waste gate? Here, the boost pressure will act against the spring in the canister, which will ultimately open the wastegate.

With an MSG for the aforementioned engines , it should definitely work

If you have it, take a look in SSP153, it's nicely described there.

Best regards,
Jochen

Jochen_145 wrote:

Hello Jan, You have just described the path that is followed when controlling the charging pressure in an AHU, AHH, 1Z etc.

Hi Jochen,

not quite...
I know how it works at 1Z and so on.

The 1Z-turbo has a pressure vessel directly mounted on the mechanical wastegate, and this vessel can be controlled much more finely than a simple pressure regulation on a traditional wastegate.
The basic principle is exactly the same (otherwise I wouldn't have come up with the idea), but the construction of the wastegate is just a bit different.
If I use a wastegate to create a lower boost pressure than the actual target, will the wastegate eventually open? Okay, the 1Z also does it this way, but using a pressure canister.
I suspect here is a very sluggish response from the turbo, which cannot keep up with the quick commands of the MSG.

Greetings
Jens

How does a "classic" wastegate work if not with this canister?

The AAZ, instead of the 2 m hose with N75, simply has a 10 cm "short circuit" from the compressor to the container.

As far as I know, the JX has everything integrated into a single unit, but it also has a membrane, right?

m

NO, the JX also has a can.

I only know about turbochargers with a pressure vessel.

Theoretically, one could imagine directly controlling the bypass valve with the LD. But here, too, I would need to provide an area for application, and we are essentially back to Martin's example.

Furthermore, it will be important to thermally decouple the intake duct pressure, as otherwise the air will be additionally heated by the exhaust turbine, expand, and the bypass will further open.

Another completely different approach would be to blow off the intake air. Here, nothing more is regulated regarding the turbo.
The Mitsubishi Patjero worked in a similar way to the G40/60 system.
Here, the turbo must have sufficient RPM stability.

Best regards,
Jochen

dieselmartin wrote:

So, how does a "classic" wastegate work, if not with this canister? The AAZ, instead of the 2 m hose with N75, simply has a 10 cm "short circuit" from the compressor to the container. As far as I know, the JX has everything integrated into a single unit, but it also has a membrane, right? m

However, the characteristics of the "Short Circuit WG Regulator" will be different from those of 1Z etc. WG turbo systems.

The question is likely how effectively this would work if we were to modulate the feedback size of the JX part to control the LD.

The TDI WG control system is a cascade control system, almost as described in the book, but the outer control loop (MSG) does not provide the control variable for the inner control loop (Dose-WG), but rather modulates its feedback variable. (Which would be the spring tension) But mathematically, the same result comes out.

[code]Another completely different approach would be to blow away the intake air. Here, nothing more is regulated regarding the turbo.
The Mitsubishi Patjero worked in a similar way to the G40/60 system.

In the G40/G60, nothing is discharged. The charging pressure is only controlled by short-circuiting the compressor outlet with the inlet. Through a valve that is rigidly coupled to run in the opposite direction to the throttle.

Furthermore, there are also wastegates that are only operated on the exhaust side.

With the G40/G60, nothing is blown away. The boost pressure is only controlled by short-circuiting the compressor outlet with the inlet.

Where is the difference between venting into the environment and short-circuiting the compressor outlet into the inlet?

There is no, except that the air must pass through the filter again before it reaches the compressor, therefore similar

Quote:

What is the difference between venting into the environment and short-circuiting the compressor outlet into the inlet? icon_eek.gif There isn't one, except that the air has to pass through the filter again before it reaches the compressor, therefore, similar.

One can view it philosophically or technically...

You have just described the path that is followed when controlling the charging pressure in an AHU, AHH, 1Z etc.

The AHH actually has a VTG turbocharger

In the Passat, model year 2000, not

An AHH is a EURO3 AHU with a 11mm pump.
Shouldn't it also be called ALH with VTG?
Best regards,
Jochen

Also auch im Passat (2000) ist der AHH ein VTG. For example, in the VW Golf, ALH The identifiers for the Passat and Golf are no longer the same from 96/97 (3B) (side-by-side and longitudinal construction). They only become partially identical from 3C and with the platform construction.

Hello young man,
dann erklär mir bitte den bei VAG checkheftgepflegten, mit dem ersten Motor ausgestatteten Passat AHH meines Kollegens, der einen Bye-pass Lader bei genau diesem Motortyp hat.

The MSG is an MSA15 (?, 038 906 018 FS) and not yet an EDC15. Also, flashing is not yet possible.

A return to bypass loaders is likely impossible.
The log data shows the typical (relatively late) LD construction of a bypass charger.
The hysteresis ratio is 84% at low speeds and no LD, and 4.8% at high LD when the bypass is open.


Best regards,
Jochen

I had one myself last week on stage. AHH with VTG loader, 11mm pump piston and smaller nozzles. I unfortunately don't know what you had, but this one now has a GT1749, 0.216 nozzles (and a new clutch in the near future ). If you have access to the repair program or ElsaWin, you will see that the loaders from AHH/AVG/AFN are identical . Part number for all 3 (currently) 028 145 702 HX


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Hello young man,

Apparently, it's some kind of hybrid model that has been created between the actual model ranges. The control unit is actually 'too old' for this year of manufacture.

My Audi is also a hybrid, as it is one of the first models from 1998, but it was first registered in 1997.

What is now much more important to me:

How big were your 'little jets' at the AHH?

But not 'normal' 0.195?

Best regards,
Jochen