[csnyder]

This goes back a LONG time - to about 1978, but I found when I had by Fiat ElectraMobile conversion (128L coupe) half worn fabric radials were the lowest rolling resistance I could get. WAY better than Bias ply or steel belted radials.
High profile (155 80?) 13 tires run at 35 on the front and 40 on the back (batteries in the rear - 8 GC2H 6 volt golf car batteries) worked as well as overinflating.

with a top speed of 50MPH and a maximum range speed of 30MPH aerodynamics were not a priority for me. I did lower the front struts and double up the rear transverse leaf spring to get the nose down where it belonged - - -