What size spacer to fit 2001 z06 17x9.5/18x10.5 rims on a 79 Formula?

[ModifiedBeasts]

What size spacer to fit 2001 z06 17x9.5/18x10.5 rims on a 79 Formula?

2"? 2.5" will it make the rims stick out past the fenders?

[SLO_Z28]

49mm front spacer would work for a 9.5 up front, and a 58-65mm spacer on the rears, depending on your cars exact measurements, and it will probably be different right to left.