Question about spacers to fit late offset wheels on early offset 951.
 

I've picked up a set of 18" 2002 Carrera 5 spoke lightweight wheels, 18x8 (50mm) with 225/40ZR18's, and 18x10 (65mm) with 285/30ZR18's for my '86 951.

http://forums.pelicanparts.com/uploa...1288029848.jpg

Lots of searching has revealed some information about which spacers to use for fitting the late offset wheels onto an early offset 951.

We can use most 17 and 18 et 50-65 mm with 1 to 1.5 spacers.

Largest wheel fitment without fender modifications: Front 18x9 et 52 with 1“ spacer, Rear 18x11 et 45 some cars may require 1/4" spacer and should require the top shock tower bolt to be reversed. Sounds like I won't have a fitment issue on either end and won't have to reverse the bolt.

Based on this information, I should need 1" spacers for the front and 1.5" spacers for the rear?

I woudl think depending how "original" your suspension and ride height and alignment is, those rears could be begging to get caught on a fender lip.

As for the math, it sounds like you are on the right track. (Current ET-OldET ... 50-23 and 65-23).. and in this application, the use of "adaptors" might be better than "spacers"

You've got a good point about the suspension, it's probably all original with just 88k miles on it. I have plans to lower it a bit and upgrade to Bilstein's.

As for adapter's, aren't those for running a different bolt pattern and spacers provide additional offset? At least that is how I've always understood it.

I'm trying to get the adjusted offset somewhere in the 30-40mm since that's been shown to work on early offset cars. A 40mm offset 18x10 will fit with no spacers, so adjusting the rear in the area of 35-40mm should work. And the front with a 30-35mm adjusted offset should work, too - well, mathematically.