I came across these today so thought I'd share for any fellow Z3 owners interested - I was going to post this in the Z3 section but got a row off Ian for posting something else which wasn't 'techy'! LOL! - so I *think* this is the right section as they are to do with essentially tuning parts?? - maybe not? I hope so at least as I don't want the mods working OT on my behalf!
You might find these useful to see what products ACS and Hamann offered the Z3 as both don't provide pictures/details of these on their websites any longer (given the age of the cars as they tend to focus on the newer models) - these are purely for informational purposes only and to validate what official offerings were provided by ACS and Hamann.