Any way to increase the mpg on a Chevy 350?

yes , no.
79 bad year mileage, archaic , medieval methods of "smog" control, improvement difficult, plus have heavy vehicle, , takes energy move heavy vehicle. try of of these, see if helps.
1. make sure fuel delivery system rebuilt/clean/adjusted properly. if has been awhile since last carb rebuild, that, adjust secondary comes in later in throttle travel, , keep foot out of throttle.
2. check compression on cylinders, if low or 1 markedly lower others, find problem, either valve seats, valve seals, or rings, compression normal amount engine, less 130 red flag in imo.
3. make sure tires inflated, make sure front end not engaged (d/c hubs, if don't have ability, consider taking front drive shaft off) while highway driving, , keep acceleration in normal amounts.
these pickups tons of fun, hard on gas pump, if right...hope helps.

i have 1979 chevy 4x4. has 350 5.7l. i'ls there way mpg?

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