Space saver from an E46 will fit fine. We had the same problem & after some advice from "Dakar" got one from Ebay for £45 in perfect unused condition.
Is it a 115 90 16?
It is a good idea to look after your spare, if it is in a bad way, there are plenty on e bay. The staggered wheels don't make any difference. I did 300 miles on mine last year after wrecking a tyre on the Lakes trip. Others on here have had similar experiences.
Yes. I think the original was the same size as yours but the 115 90 16 from the E46 fits with no problems.
Leave it hidden somewhere to collect later
Carry a good set of luggage straps and a microfibre towel and strap it to the bootlid.
And yet most people (like myself) hate runflats with a passion! First thing I did on my Z4, and it completely transformed the car! Get rid of the runflats!
Standard spare size is 125 90 R15, the 115 70 R16 is 1.6” (6.7%) smaller in diameter so it would fit the carrier, albeit rather loose but I wouldn’t want to use a spare that much smaller than standard.
True, but I still think too small for a Z3, not an expert but could cause damage to dif on rear and handle on front?
