Been doing some internet research (again - im surprised how something that must be so obvious isn't easilly found) and have located one - and only one - reference that it is a 55 trim. No diameter however.
I'd prefer it if someone could verify it - unless of course no-one knows and just swaps out because that's what the last person did

http://not2fast.wryday.com/turbo/maps/ MAPS

http://cherrypicker.tripod.com/id1.html WHEEL SPECS

cheers,

I'd actually already found both those pages - and as the diameter's page didn't specify the turbo model or anything, and as the site is related to a 'Z' i assumed that he was referring to the turbo's that were as standard on the engine range he's interested in...

I've found pages after pages on the net referring to 'T25' and searched until my eyes have started watering There is just so much un-verified data out there! As an example, note also from the 'maps' link, there are two 60-trim maps!

oh well - I'll wait to see if anyone can give me a 100% guaranteed, accurate, verified answer that they can swear by! Or I'll just have to go and disassemble mine, just to determine the trim. Even then, I'm without a verified map...