I have a 72 Skylark convertible! I finally got my 15X8" custom ralleye wheels with a 5 1/2" backspace from Specialty Wheels and they look great!!! All of my measuring and reading the trials and errors on this board paid off! My tires do not rub and will not rub on either side, I have 5/8" space in the outer lip and 3/8" on the inner. Here is what I did. I measured my minimum wheelwell width which is 13". My 295/50/15 tires are 12.4" wide so I had no room for error. I then found the center of my wheelwell which is 6 1/2" (13 divided by two). Now I needed to see if my drum face was in the center of the wheelwell, it is not! I have 7 1/2" from the drum face to the inner wheelwell and 5 1/2" from my drum face to the outer fender lip. This meant that I needed to move my backspace in 1" to center the rim in the wheelwell. (Move the rim in 1" to make it 6 1/2" on both sides of the drum face) To find the center of a rim you take the advertised rim width and add 1" to it, so lets do my 8" rims. They are advertised at 8" so I add 1" to make it 9", then I take the 9" divide by two to get the center of the rim which is 4 1/2" then add the additional 1" from my above drum measurement for a total of a 5 1/2" backspace. This should help us all to figure out the backspace and maximum wheel size for our cars! Good luck on your project! Tim
I made a mistake on my backspace measurement, my backspacing is 5" not 5 1/2". The 5 1/2 will not fit with the 295/50/15! Sorry for the confusion. Tim
