strange about the ohio winter gas causing running issues like engine bucking, ive been in iowa my entire 30+ driving years & have never noticed much difference in how my daily or classic cars drive come warm spring days. the summer blend isnt used until may1, plenty of very warm days by then. winter blend starts sept1, still plenty of warm days into mid sept in my area, it can be in the lower 90's till mid sept.
my pontiac engines are stock, mild built, & 10.75:1 500+hp, none of them act much different in starting or running with either winter or summer blend fuel. worst thing i get on the hottest summer days after hard drives with summer blend premium fuel is a occasional slight run on when shutting off the 500hp engine, but that is more due to carb throttle plates being open a little too far, i adjusted idle speed down & its almost gone.
im sure different blends can act different for some engines, but just like vapor lock or overheating, storing fuel issues, etc, ive been lucky enough to never deal with that on any cars ive had from SBCs to carb'd foreign or classic pontiac v8's.
