What is the best mileage anyone gets running a 289 or 302 on the freeway?.....I am thinking of swapping the 352 ci (15 mpg) with a 3 speed stick tranny in my 1966 Ford pickup truck with dual exhaust, to a
289 or 302 and adding headers, a dual plane manifold and a flex or electric fan in hopes of getting over 20 mpgWhat do you guys think?
Much Obliged Patrick