Smallblock efficiency or How to have your cake and eat it too

The biggest thing anyone can do to improve mileage and efficiency is a tune up and changing your driving habits - going the speed limit most importantly.

I’d only trust GPS for distance. Not an imperfect speedometer and tire size.

And what do we do about all the different fuel blends and grades? E-free, E-10, E-15, winter blend, summer blend. Not to mention all the different fuels internationally. I run E-85 and my fuel mileage sucks! It’s pretty obvious as to why - less BTU. So many more variables to list. I think a big takeaway on discussions about fuel mileage is that when someone mentions their fuel mileage - how do you believe them? X miles per gallon is useless info unless you’ve used GPS for mileage and measured the fuel going out accurately.