Redline Tire size - 67 GTO
 

What is the largest size 15" tire that you have been able to run on a 66/67 GTO without scrubbing? I currently have 215/70/15 Whitewalls on 15x7 Rally II's. The next set will be redlines and I would like to go a little larger if possible.

Thanks in Advance.

275/60R15 rear tires on the 67 rear end which includes late 66 axle width. Requires a custom 8x15 Rally II rim with 5-1/4" backspace, trimming the outside fender lip, and tapping the inside inner fender over frame in slightly so it sits slightly in from frame rail. Have my cars done and helped another half dozen or more club members with their cars and tires do not rub. Skip any of the above three requirements and you have to go smaller on the tire's section width. Doing the above allows almost 12" of width inside the wheel well and the 275 tire mounted on an 8" wide rim is right at 11" wide.

Believe one club member is running 255's on a stock 7" Rally II rim with the 4.25" backspace and the car has to sit a little higher in the rear or he gets minor rubbing.

Here's a photo of the current wheels on my car. While I was running the custom Rally II's, the car originally came with the dog dish hubcaps so I have went back to black 8x15 steelies with the poverty caps and the 5.25" offset. The car sits at standard ride height.

Not sure if this helps as these use the 65 rear width.

275/60/15 on my 66 with a early style (1965 Chevy) 12 bolt. Wheels are 15x8 with a 4.5 back space.

255/60/15 on my 67 with a early 10 bolt (65 GTO rear) 15x7 Rally II with a 4.25 back space.

If going new wheels with a 4.5 backspace you should be able to put a 255/60-15 on with no problem,

Here's a shot of mine with 255 60 15's on a readily available 7" Rallye II,

What is the backspacing of your wheels? Still running drum brakes? Any other deviations from stock in terms of suspension?