3:55 gears on the street

69_340_GTS said

25.5" tires will fit just fine. At stock ride height The 225/60-15 tires fit on my '69 Dart just fine, front and rear. Rear tire can easily be up to 28", but personally I like them all the same size. Either your car is severely lowered or you have the wrong size/offset wheels, if 24"s are all you can fit on it.

Click to expand...

I did my tire template clearance checks w/o torsion bars installed, so I could easily achieve max suspension jounce/rebound. For the jounce condition, I slightly compressed the jounce bumper to simulate a worst case condition. During "normal" driving, you will probably never see this condition combined with full lock steering.

However, when simulating larger diameter tires, I actually had a clearance issue with the suspension at a more normal height and with the tire turned only slightly. The outer "corner" of the tire would get very close to or touch the bottom corner of the front fender. I think this issue is more prevalent with lower profile tires. Tires with a higher profile/sidewall often have outer tread widths that are less than that of the same nominal width tire with a lower profile. In other words, a 225/60-15 tire may have a tread width that is smaller than a 225/35-18 tire, even though they are both 225 width. The skinnier outer tread width creates a less "square" tire profile and can increase clearance to the various components. Of course, there is also variation between tire brands/designs.

FYI, my 18x8 wheels have the same offset as the 1975 Dart 14" steelies that were originally part of the car from which I removed the front suspension/brakes to install on my '68.
https://www.summitracing.com/parts/RPM-TTR16-886550

I spent many hours analyzing and measuring before I bought my new wheels and tires, and this seemed to be the best package I could get that was guaranteed to fit under all conditions.