where can i find info on original wheel size for my car. 1987 635csi, vin #WBAEC8400H0614402. previous owner installed some 15" gangster wheels with mirror tint on the windows to boot. car is for sale , needs tires , thought i might look for original rims while i was at it. thanks for any help

Found this info on e24 wheel sizes that may help you out some:

6x14" = 22mm offset

6.5x14" = 22mm offset

7x14" = 18mm offset

7x15" = 20mm offset

165TR390 = 22mm offset (TRX)

195TR415 = 19mm offset (TRX)

Keep in mind that a lot of other BMW wheels will fit your car too, all 5 series (e39 will need hubcentric rings), all 7 series, and the 8 series too. I think the sixer looks great with 17" wheels, you may get lucky and find a set cheap. Here's a link to check out and help you get your car ready for the sale if you have little things that need attention:
Big Coupe Group (http://normgrills.net/bcg/)
Good luck.

this thank you is long overdue. and especially for the link to big coupes, as this car develops new issues as fast as the old ones are fixed. tr.