Best Top 10 Bolt Ons For a 318

Economy???

My dad had a 76 Charger with a stock 360 2 bbl that got 20 mpg on the highway... 360's can get good economy if you build them right....
My 76 charger (1st car, hand me down from Dad) sure didn't when it had the 360 in it, when dad got it.
My dad was the one who wrote down EVERYTHING including every qt of oil, every tank of gas, what mpg the last tank got, what station, cost of fill up, etc.
He was the one who decided to swap to a 318 in that car before I even had a license. I don't remember what was actually wrong with the 360 that got yanked, but I do remember we put the distributor and carb/intake from the original 360 into the 318 that went in, and then (among other things) started getting way better mileage. And as I remember even dad saying (remember now I never got to drive thru car with that 360 as I didn't have a license yet) how that car was no slower with the 318 than it had been with it's 360.