Nozzle Swap: VP vs PD

As is commonly known, when simply replacing the injector nozzles, the opening pressure needs to be adjusted. However, this can be avoided by purchasing completely overhauled injector holder assemblies that are pre-set and tested, making them ready for installation.

Not too long ago, there was a change in the shop regarding the PD Tuning injectors, moving from complete PDE injector units to just the injector tips. The video clearly shows how to replace the tips.

BUT:

Why is it then that nothing more needs to be adjusted on the PDEs (apart from the work that also arises when swapping them with serial nozzles)?

Does increasing the hole diameter while maintaining the same opening pressure not worsen the fuel atomization?

Theoretically, it might be possible to increase the opening pressure of a PDE element by modifying the spring within it.

It would also be interesting to see reports on how the installation of the nozzles has changed the smoke behavior. I'm aware that an ECU remap (SW tuning) is necessary, but in this case, poorer atomization has a mechanical cause.

It would be great to get some answers here, perhaps even from the homeowner himself, as these nozzles are likely to be my next modification.

Best regards,
Alexander.

Yes, but in the PD element, there is no opening pressure. The fuel only flows out when the solenoid valve is de-energized by the control unit!

Hi,

Quote:

It would also be interesting to see reports on how the installation of the nozzles has changed the smoking behavior...

"There's no smoke if you do it right. However, due to the significantly larger hole diameter, these nozzles aren't really suitable for ice cream machines that only rotate in the first gear, as the consumption increases considerably."

Software customization is essential, so please refrain from end-customer inquiries like "how much horsepower will I get if I install these injectors?" This article is intended for use with your own customers and for tuners who are capable of adjusting the engine control unit software accordingly.

Best regards, Rainer.

Yes, but in the PD element, there is no opening pressure. The fuel only flows out when the solenoid valve is de-energized by the control unit!

Does the solenoid valve determine the injection duration and timing, or am I completely wrong about that?

As far as I understand, the injection pressure for the pilot injection and the main injection is determined by springs.

'Opening pressure' might be poorly phrased...

Best regards,
Alex

Hi,

It would also be interesting to see reports on how the installation of the nozzles has changed the smoking behavior...
'There's no smoke if you do it right. However, due to the significantly larger hole diameter, these nozzles aren't really suitable for ice cream machines that only rotate in the first gear, as the consumption increases considerably.'

Software customization is essential, so please refrain from end-customer inquiries like 'how much horsepower will I get if I install these injectors?' This article is intended for use with your own customers and for tuners who are capable of adjusting the engine control unit software accordingly.

Best regards, Rainer

Yes, as mentioned above, I was aware that these cannot or should not be simply installed.

I like the ice cream parlor circle...gg...

Figuring out how many horsepower the injectors alone produce would be about as smart as asking: How many horsepower do I gain if I remove the catalytic converter from my TDI?
Well, at least 20, isn't that obvious?

@Rainer: I noticed that the pistons are missing from the list of components in the large Stage 2 PD package. Are they not needed, or were they accidentally omitted from the list?


Best regards, Alex.

Hi,

Regarding the pistons, there is now a different solution available, which has some drawbacks, but it saves time and parts.

Best regards, Rainer.

Hi,

Regarding the pistons, there is now a different solution available, which has some drawbacks, but it saves time and parts.

Best regards, Rainer

Ah, that sounds interesting!

In what ways do disadvantages arise?

Greetings, Alexander!