what back space & tire size?

[87-TURBO-T]

thinking of going with 18x8 and 18x9.5. what back spacing should i get? also what tire sizes? car has stock springs. thanks

 

[87-TURBO-T]

found some that are 4.5 bs front and 5.3 bs on rear, will they work?

 

[EB1STGN]

Fronts will work, rears won't without a spacer. Rears will need at least a 1/4" spacer and a 275/40/18 tire. nothing wider.