Date registered: Feb 2010
Vehicle: 1972 280SEL daily driver. 904 Dark Blue with cognac interior. euro 4.5 engine
Location: Williamsburg, VA
Mentioned: 3 Post(s)
Quoted: 36 Post(s)
Well, my obvious first question would be what size is on the car now. Absent that information, if the car originally came with Bias Ply tires, they were likely a 185HR14....185 being width and 14 being rim diameter. The problem with the old bias ply specs is that aspect ratios were different (and much taller). Typical aspect ratios for bias ply were 80-90 although toward the end, they were producing bias ply tires with ratios of about 78.
So, a 185HR14 with an aspect ratio of about 80 is equivalent in diameter to a modern 195-75R14 or between a 205-70R14 and 205-75R14.
I personally am running 205-75R14 on my W108 chassis because I wanted a little wider tire and the higher aspect ratio slows highway RPM just a bit. No issues with rubbing. I think they fill the wheel wells correctly.
I chose Hankook tires ($61 at Wal-Mart) because they are one of the rare white stripes left.