Jet Tuning: Registration Possible?

Hello everyone!

Inspired by a thread I saw here, I was wondering if it might be possible to get jet tuning approved/certified.
If you install injectors from a 110 horsepower engine (e.g., AGR, ALH) into a 90 horsepower engine, you are essentially converting it into an AHF or ASV engine.
The combustion process should largely be the same, as the pump and injectors are original components from the VAG group. The target boost pressures are also practically identical. The only "minor issue," in my opinion, is that the engine control unit (ECU) maps are not adapted to the ESP-DHK combination. However, this combination typically leads to fewer soot problems than many chip or tuning boxes with certifications.
What are your chances of convincing a TÜV inspector to approve this combination?

Regards,
Alex.

Hello Alex,

Problem:

Whenever a modification is made to the fuel system that is expected to worsen exhaust emissions, an exhaust emissions test is required. This costs several thousand euros.
But do you think anyone would notice the difference, even if they looked at the nozzles?

Best regards, Uli.

@Uli S.:

Quote:

Whenever a modification is made to the fuel processing system that is expected to worsen the exhaust emissions, an exhaust emissions test is required. This costs several thousand euros.

What I was trying to say is that the exhaust composition of a modified EGR/ALH engine will differ only slightly from that of an original AHF/ASV engine.
On the other hand, I believe that some chips have a significantly larger (negative) impact. Therefore, the emissions classification should ideally remain the same (at least for AGR systems, Euro 2).

Quote:

But do you think anyone would notice the difference, even if they looked at the nozzles?

Simply looking isn't enough; you have to at least remove the mounting bracket to decipher the part number. However, my main goal was to find a way to legalize the modification, so that you can drive with it legally, even with aftermarket exhaust systems.
Who knows what kind of investigations are carried out when someone is involved in a serious accident?

Regards,
Alex.