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928 78-85 Can use all of the narrow body wheels from 993-986-996-997 50mm -65mm et front and 48mm - 65mm et rear. 1981 to 1984 cars have 21mm spacers in the rear. These can be removed to fit some wide body wheels. (18x10 40mm 18x11 45mm) You may still need to do some fender mods depending on the tire size.
Most extreme fit 18x10 et65mm front and 18x11 et45mm-63mm. The 18x11 et63mm wheel fits nicely on the rear with a 285/30/18 tire. 19"s fit very nicely on the car
18x8et 50mm and 18x11et 45mm below
928 86-91 Can use all of the narrow body wheels from 993-986-996-997 50mm -65mmet front and 48mm-65mm et rear. Some manual 89gt cars have 17mm spacers in the rear so you may have to chuck them when using wider wheels and tires
Most extreme fit 18x10 et65mm on all four corners. The 18x11 et63mm wheel fits nicely on the rear with a 285/30/18 tire. 19"s are possible
18x8et 50mm and18x10et 65mm below
928 GTS Can use all of the narrow body wheels from 993-986-996-997 50mm-65mmet front and 48mm-65mm et rear. Cars have spacers in the rear for the flared fenders. These can be removed to use wide body wheels.
Most extreme fit 18x10 et65mm on all four corners. The 18x11 et63mm wheel fits nicely on the rear with a 285/30/18 tire. 19"s are possible
18x8et 50mm and 18x10et 65mm below