Thinking of 27 in diameter tire/wheel options for 55 C4

[chevynut]

I will try and make the 255/45-18 tire work, since I like the bigger diameter, and they worked so well on my 96 Impala SS with the Goodyear F1's I ran, with lots of tire choices. Just on Tirerack they have 64 tires to choose from in that size, versus 2 tires in a 255/50-17. thanks for the input.

Those two tires virtually identical diameters. Are you wanting the larger diameter 18" wheel?

American racing makes the torque thrust wheel I like in a 17x9 with 45mm offset/6.77 backspace that is the C4 fitment. To go with 18's the custom shop can make an 18x8 with up to 41mm offset, or a 18x9 with up to 54mm offset.

The 45mm offset it going to make the front tires 68.5" wide which I think might be a problem, and the 41mm is worse. The 54mm offset makes it 67.79" which I think is a better fit for a 255 tire. I don't know how your frame is designed behind the k-member but I think that combo would fit in my frames. When you're pushing the limits like this, the only way to tell for sure is to try them. I recommend doing it without springs, turning the wheels lock to lock, and moving the suspension all the way up to the top of it's travel.

The inboard clearance is my biggest concern at this point, but I also want less positive offset so the wheel has a little deeper dish to it.

The good thing about that scenario is you can always add a spacer.

[rockytopper R.I.P 5-13-2017]

Dog thanks for input on 255/45/18. I have also been looking at putting 27 inch tall tires on all 4 and was looking at 255/50/17 but tire choices are minimal as you point out. I will probably still go with the cheap Nitto 555 on my first set I like them they are on my current ride 255/45/17 but it is nice to know they are way more options in that size. Including going to an all season if I wanted. FYI I have clearance issues on the inside front on stock suspension lol. I hit the sway bar. I might have to customize it and flatten it out on the ends like the pro-touring guys to fit more tire in front and retain steering radius or most of it.
Rocky