One of those things that comes up repeatedly around here is the thorny issue of rear suspension ride height and how to improve cars that may be sagging. I'm not going to present a solution to that question, as there are quite a lot of variables involved. What I have put together though is a summary of the different spring/damper combinations used on the rear of the Superb which should cover most of the possibilities for those who want to stick with OE parts if they're modifying their stock configuration; this is attached here as a pdf along with the geometry table from the service manual.
Some caveats:
I don't have access to a dealer version of ETKA, only some online versions: the information may not be complete as a result (come of the online catalogues are buggy at times)
Even assuming that the catalogues I've found are complete, there may still be data missing from the catalogues
I've come across a few inconsistencies that I've had to make an educated guess on
What you do with this information is entirely your own business:
I've done the best I can but if you mess up your car using it it's not my fault
Changing the rear suspension without also changing the front could be problematic
I'm planning to do a similar exercise for front suspension when I can make some time for it
Some known issues:
There are two raised ride height configurations available but I can only find information for the lower of the two (+10 mm over standard)
The raised ride height configurations I can find seem to be listed exclusively for the 4x4 model
I've no idea if the FWD model had this option or not and can't find information on it either way
Some dampers in 1JA have a VIN split listed for the P/Ns pre-facelift
This is included as an additional line in the table for the post split numbers
In 1JC there is an additional damper part number listed with no associated spring PR codes
It's listed as 'Other?' in the table
In the main table, the lines highlighted in green represent the spring part number while lines highlighted in lilac represent the damper part number. To look up a configuration, find the weight range PR code at the top then drill down to the damper PR code on the left. every spring/damper PR code combination has a unique spring/damper combination.
The additional tables below this are to explain/clarify what's going on. The weight range assignments are a relative ranking of the spring stiffness with 1 being softest, 14 being stiffest. As you can see in the table, the part numbers for a given weight range vary depending on the chassis/damper spec e.g. 0YB for 1JA is different to 0YB for 1JC, etc. Not every chassis spec includes all weight ranges. What is consistent in the springs is the relationship between paint codes and part number (with one exception: 0YA and 0YB for 1JC have the same paint code but different P/Ns - probably an error in the catalogue). Weight ranges 11-13 don't appear to be assigned on the Superb based on what I can find in the catalogue.
An interesting thing that jumps out is that the spring alone does not determine ride height. In the table, 1JA/0YG uses the same spring as 1JD/0YA, even though the latter is 10 mm higher: the damper is what adds the extra 10 mm.
The four damper configurations listed in the catalogue are fairly self explanatory. As noted above, the higher of the rough road combinations is not listed in the catalogues I have access to. Greenline is not listed in these, but the common opinion is that it's using the Sport chassis.
rear suspension PR code summary.pdf