Slant 6 MPG Upgrades?

One of the huge fights you have, which people don't take into account is FUEL. Alcohol --izz--eeed fuel --you need more of it, and the more alky content, the more fuel you need.

Frankly, I doubt the money you will spend on MPFI vs TBI will be worth the trouble. Find a 1 or 2BBL TBI setup and run it

You for sure want to run a setup that allows the EFI to control spark advance

Pick an EFI that has a companion display so you can see what is going on. One key to better mileage, other than a light foot and lowered cruise speed, is high advance numbers at low throttle settings