Originally Posted by
refried
I used to run a Chevron station and my fuel came from a Tesoro refinery, the Chevron additives were added as the truck was being filled.
I've made several hundred trips to Baker in my Subaru that now has 400,000 miles, If I filled my car with 91 octane I'd use 7.5 gallons on the 225 mile roiund trip. If I used 87 octane I'd use 9.5 gallons, If I used 87 with alcohol I'd use 10.5 gallons. This was every trip, same roads, same traffic, So in my experience I'd say I got better milage using premium fuel.