On my '70 with 70 12-bolt rear end stock width, would a 295/40/18 on an 18 x 11 wheel fit? The outer wheel lip has already been trimmed, no other mods. The nitto 555 g2 are 27.2" tall with an 11.8" section width. Their website says they will not fit on an 9.5" wheel, thus the 11". I plan on near stock ride heigth.
Well I answered my own question. Using a tire/wheel of known dimensions (approx. same tire dia.), I took careful measurements while articulating the rear differential through it's range of motion (springs removed). What I found was that I have 1-1/8" and 1-5/8" minimum clearance to the outside and inside respectively, for both sides. This was with a 10" section width tire so a 295mm (11.75") s.w. will leave about 1 inch to split betwen in and out. This should leave 1/2" to either side if the tire is perfectly centered in the well. The OEM 15x7 rally wheel I used has a 4-5/16" bs. So it looks like 4-1/2" bs or 1/2" offset would about center that tire in my well. So for an 18x11 wheel, I'll need a 6.5" backspace. This is in a 70 with a 69 12-bolt (just under 61" wide, wheel mounting surface to mounting surface) and aluminum brake drums, stock well sheet metal. The closest point to the outside was to the top part of the outer wheelhouse (on the inside obviously), not the trimmed qtr lip
Did you include the sidewall bulge in the width? Also, you can't assume it is centered in the wheel well. You know how clearences are on these old cars. Also, even if it is centered and clears the body will sway left to right a little during spirited driving and could rub the tires. I don't think 1/2 inch is enough clearance IMHO. Sent from my iPhone using Tapatalk
