The SRM II Cooper 215/85R16 on my standard 4.5" 1954 rims has a diameter of over 31" (loaded diameter). The Cooper SRM II specified diameter (on wider wheels) is about 30" (unloaded diameter?). The 6.50x16 original standard tire had about a 28" loaded diameter.

Tim
1954Advance-Design.com
1954 3106 Carryall Suburban
1954 3104 5-window pickup w/Hydra-Matic
The 216 and early 235 engines are not "splash oilers" -- this is a splash oiler.