18" wheel fitment questions

[ILLEGAL REGAL™]

Hey all, I'm looking into scooping up an 87 as a daily driver and would love to put some 18's all around. It will be lowered via front 2" spindles and rear lowering springs.
My question is what width and backspace is needed?

What size tires are optimal for the front, and the for the rear, I'd like the widest wheel/tire I can fit. Frame notching and rolling the lips will be done to accomplish this. And if the a-arms need clearancing that would be done also.


TIA

 

[Royal-T-Ltd]

Call Jeff @ Group A Autotrend, he's dealt with these cars for a while and can give you good info. HTH

 

[FBSideoiler427]

Big fatties on a GN

An 18X11 With a 5.265" bs should fit with no modifications to the frame, but might need the lip rolled, or graft on a GNX flare and relieve the top circumference of the flare/lip.

If you have the luxury of notching the frame, 18x12 (6.265 bs) or 18x13 (7.265 bs). Keep us posted on your frame notching venture.

you should be able to squeeze a 265 tire in the front. Any wider and you need to start addressing the scrub radius which will affect upper and lower control arm configuration and geometry as well as kingpin angles.