I use to fly PA 18 150s on mogas in the early 80s glider towing. the best fuel was the old 2 star, lead content i belive. Later we had to fly on 4star as 2 star was not approved.
There were no problems with the Cub but big problems with other types Chipmunks had to leave the cowlings open after shutdown otherwise the fuel will boil in the main pipe next to the engine block. The supermunk was a disaster, lost count how many failours i had with fuel vaporisation. As soon as it vaporised you would lean out till you got to the point where it would rich cut & lean cut at the same time very sporting!
