I used 26×10.5-15, basically same height and similar width on 76 SS3 15" rims. I assume those 14x7 also have 0 backspace. They just touched the frame with 8 psi at the track, otherwise fine. Considering these are an around town tire, radial tires on the front is fine. I have on my 70S currently and did on my old 77 van. Just have another set of tires/rims, if you hit the open road.