I live in north east ohio so we can get a wide range of weather/temprature.
The higher the octane the smoother my van starts and runs.  it ran REAL GOOD
on
av-gas left over from formula V racing ( just had to try it once ) . I will
do what ever works so it is worth the money in my case. As far as recomended
octane my bentley
states"Do not use any fuel with octane ratings lower than 91 RON" . Hope this
helps.

Jim Morgan 86GL " Breadbox"