Might be able to get hold of some cheep aftermarket 17" alloys which were fitted to a Z3 , this is only temporary while my alloys go for refurb will they fit ok ?
Generally speaking yes they will fit.
The staggered Z3 set up is 7.5'' front and 8.5'' rears with an offset of 41
The Z4 staggered set up is 8'' front, offset 47 and 8.5'' rears with an offset of 50