Why Better Mileage with Premium Fuel?
I know high octane does not magically produce more horsepower or make a car faster. I know it's probably psychological when guys claim their car "runs smoother" or something when using premium gas. But here's my hopefully objective observation...
When I run premium fuel in my Versa, my average fuel economy is 1-2 MPG higher than when I use 87 octane. I know my manual calls for 87. I know I'm not driving a Corvette or some turbocharged V6 that calls for 91 or 92 octane. Yet the numbers are what they are.
Could anyone explain this? Does a humble economy car like the Versa have such sophisticated engine management systems in 2026 that it can listen for knock and adjust the timing to take advantage of higher octane?
Thanks!