How to calculate tire size?

I have a 68 Barracuda, for street romping.
On the front; It has been wearing 14x7s since about 2005 with a near-zero offset, I think it is 3.75 backspace. It wears 235/60-14s.
I have to run them at 28/29 psi for long tread life. But whenever the mood strikes me, I pump them up a tad; but honestly, on the street, I got used to the front end skating, and the low-pressure roll-over. Street tires in my chosen size, driven on the street,lol, just do that, I learned to deal with it or slow down..
The KH calipers will not nestle inside ALL wheels. The Rallys have the shape to fit them perfectly.