Spurred me to dig out an anecdote: 2005 Toyota Solara, 3.3l V6, vacation trip from CA to UT and back, Sept 2016, moderate A/C use: 6 days, 2550 miles, 28.9 mpg

Spurred me to dig out an anecdote: 2005 Toyota Solara, 3.3l V6, vacation trip from CA to UT and back, Sept 2016, moderate A/C use: 6 days, 2550 miles, 28.9 mpg (100% lowest-octane "regular" gas used). As others have noted, driving smoothly with minimal/gentle acceleration has a major mpg benefit.