i was searching around trying to find out how wide of a tire would be safe to run compared to rim size on a 60 series tire. i'm running spare wheel ghetto skinnies (tossed the temp tires) with m and h 185/55/17 drag radials for front skinnies. while these are really light weight, they're pretty short, only about 25" tall (regardless of what m and h's website says)
so i'm contemplating going to a taller tire to lift the nose of the car. even though it will pick up a little weight, i believe that moving the nose a little higher will help with 60' times.
after some research...not everyone will agree with this....a 4" difference in rim size to section width is about as far as you can push it. (remember that's a 60 series tire..pretty tall sidewall) that surprises me a little that a difference that wide is considered safe (it's subjective of course, it depends on who you talk to).
so i'm looking at tire that is approximately 27" in diameter that will still fit safely on a 5" wide rim