TDI Chiptuning: Is It Compatible?

hello experts,

I have a small question.
I have tuning chips (27C512) for my 90 HP TDI (1Z) engine, manufactured in 1994.

What happens if I install this in a 90 hp TDI engine, manufactured in 1997?

Do these work, or if not, why?
I can imagine that the delivered data (e.g., intake air, injection amount) are identical, or is there something else involved?

Thank you for your help.

Hi,
I'm quite sure they are not compatible.
Your old engine control unit (ECU) with 2x512 EPROM chips was an MSA12 with 2 8-bit processors. Even that had different versions that were not compatible (028906021b/c vs. 028906021p).
Since around 1996, VW has used the successor model (MSA15). This uses a 16-bit processor (Infineon C166), where the data is also stored in two EEPROMs, but forms a common data set (high and low bytes). Additionally, the EEPROMs in the MSA15 have a different package (PLCC) and are also larger (1 Mbit).
Certainly, when tuning, you have to modify the same parameters, but they are located in completely different places and often differ significantly. This is because, on the one hand, areas of the sensor technology have changed, and on the other hand, the values are already different due to the new processor architecture.