The benefit from using a premium blend of gasoline in a vehicle that doesn’t require it may not be worth the extra cost for some U.S. drivers, motor club AAA said. AAA reported a national average retail price for regular unleaded gasoline at $2.46 for Wednesday, more or less stable for the week. The average price for premium gasoline was $3 per gallon. The motor club said its research showed that the difference between regular- and premium-grade gasoline has increased from a historic norm of 10 percent to now at least 25 percent. For some vehicles, the higher octane premium blend means an improved fuel economy and better vehicle performance overall. “AAA’s testing reveals that drivers could […]