Spare Tire Diameters with POSI Unit

[Jon69RagTop]

I'm trying to organize a spare tire combo unit that works with the big brake set-up I have. I've purchased a 2005-07 GTO spare, and with a 1" wheel adapter the rim fits over brakes both front and back. (KORE 3) The wheels adapter is barely necessary, and some might hack on the caliper but I'm not.



The temporary tires diameter is 25.375, but the rear tires on my car are 26.5" tall> I've found a M H front drag skinny which fits the GTO rim-185/55R17, and the diameter of the one is 26.0.



My question is would this 26. diameter be close enough to the 26.5's to not create stress for the posi-unit? Obviously it's only given the need for temporary driving in case of a flat tire?

I could also scrap buying the 5/8" taller tire and just go with a good fix-a-flat kit. The GTO spare would then be good as is for the fronts, and fix-a-flat for the rears. Anything beyond a fix-a-flat for the rear and I'd be S.O.L. on a long road trip though, like Power Tour etc.



I'd appreciate any other ideas or feedback.



Thanks