280SL FIP types and differences

[Berggreen]

Hi All

I am trying to become more knowledgeable about the differences between the late [without start solenoid] 280SL fuel injection pumps (FIP), which I understand differ between the European and US markets:

R22Y: US market
R24Y: US market ("simplified" R22Y)

R23: European market
R25: European market ("simplified" R23)

I can see some of the differences in the manual (https://www.sl113.org/wiki/Fuel/Injection), but the manual does not say anything about the functional and performance differences between these FIPs.

Eg. why have different models for different markets in the first place?

Does the US market models (R22Y & R24Y) give less HP in exchange for lower emissions compared with the European models (R23 & R25)?

What does the "simplified" mean comparing the R22Y/R24Y and R23/R25?

I would love to hear, if some some of you have more detailed insight into the differences between those FIPs, and what does the differences mean, especially in terms of performance.

Thanks,

Christian

[WRe]

Hi,
here you can find a lot of information about Bosch mechanical FIP: http://sterntwiete.mparschau.de/html/einspritzung_2.html *.
...WRe

* Information in German, but newer systems (e.g. tablets) or browsers can translate it on the fly.
Example:
The installed controller type can be seen from the pump designation on the type plate, which can have the following identifier, for example:
PES 6 KL 70 B 120 R25
The numbers here mean a pump with its own drive (camshaft) and end flange mounting for 6-cylinder engines. In addition to information on the piston size and number of assemblies, you also get the controller type, here the 25 for clockwise rotation (at 6.3: L for counterclockwise rotation). An even finer distinction in the variants of the controller types can then be made by additional labeling with letters, e.g. The controller type R24W replaced the R24.

[Pawel66]

Thanks to helpfulness of one of the Members, we can also enjoy this material in English.

[Berggreen]

Thanks to helpfulness of one of the Members, we can also enjoy this material in English.

Thank you both - that is very helpful. I will study this in detail.