Garrett VNT 15 Turbo: Fits 1Z Engine?

Hello,
'Since my 1994 Passat TDI has now exceeded 320,000 km, I expect to have to replace the turbocharger soon. This model originally comes with a boost pressure control system that regulates the amount of exhaust gas driving the turbine wheel. However, if I'm already replacing the turbo, I would like to install one with an adjustable variable geometry nozzle, as it is standard on newer models with 81 kW. My question is whether this type of turbo will fit onto the existing exhaust manifold, or whether a new manifold is also required. As far as I know, the variable geometry nozzle is controlled by a vacuum actuator, which means I should be able to simply connect the old vacuum hose and it will work. Finally, do I need a different engine control unit (ECU)? I would appreciate it if anyone has experience with this. In my opinion, the development of adjustable variable geometry nozzles represents one of the biggest advancements in direct injection engines, especially because it largely eliminates turbo lag.'Best regards,

Hi,

if you had ever used the search function...

I'm sorry, but I cannot access external websites or specific files online. Therefore, I am unable to translate the text from the provided URL.

http://www.meckisfaq.de/antworten/motor/diesel/1z_2_afn.htm

The 1Z engine has a wastegate turbocharger, and you want to replace it with a variable geometry turbo (VTG) charger. The first major problem is that the wastegate is controlled by overpressure, while the VTG is controlled by underpressure. Additionally, the flanges of the two turbos are not the same (see link below).

etc. ... etc. ...

I believe this has been discussed before (regarding a VTG loader on track 1Z).

It won't work (without a significant amount of effort). Even if you manage to find suitable exhaust manifolds and a turbocharger, and even if you can figure out how to change the boost control from overpressure to underpressure.

The engine control unit has a boost pressure map that is used to regulate the boost pressure as a function of engine speed and other factors.
As long as you don't change this map, the boost pressure will continue to be set to the old target values. Therefore, you won't be able to take full advantage of the new turbocharger.

@Passat B4 1Z

Hmm, turbo lag also depends on the size of the turbocharger.

@Everyone

Why does everyone say that VTG turbochargers provide more air at lower RPMs? I mean, my turbocharger also starts working around 1500 RPM. The VTG turbochargers just kick in harder because the engines with VTG turbochargers produce more torque when the turbo kicks in. You don't notice it as much on the 1Z engine because it only has 90 horsepower and 202 Nm of torque.

Best regards, WarLord.

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

"Hi,"

Simply put: Because the VTG turbocharger boosts pressure below 1500 [units]. See the pressure curve in the image below – this is a log of a full-throttle acceleration in 3rd gear that I did about 1.5 years ago.

Best regards,

January.

Okay, does anyone else have a log file from the 1Z system that we can compare?

Best regards, WarLord.