Around 20-ish. I was getting 20 with a 4bbl edelbrock 600 on mine, and a little bigger cam. Depends on how heavy your foot is.
A stock 302 in good running condition should get around 15 city and 20/23 highway depending on how you drive and the quality of fuel you are useing.
Also depends on which "stock" 302 you're talking about. A 72-76 302 will get fewer miles per gallon than a 94-97 5.0 from a pickup or van.
Well with over 130000 miles on my stock 1973 302 I get 21 mph on the highway and 17 - 19 in the city. Your mileage depends on the weight and size of vehicle, the gear ratios and tire size, the driver's habits, air pressure in the tires, and a number of other things.
ive got a stock 73 with 94k miles but it sat for a long time so im sure theres still gunk cleaning out from it actually being drivin is there any easy tune ups and such that could add a few mpgs?
I wud say; new plug, wires, distributor cap, rotor and points, if the car has points ignition. That's abt the easiest and least expensive I can think of.
Run the lowest octane gas you can without getting detonation - I use the lowest at the pump - (87?), make sure your tune is good; lowest idle speed without stalling, recurve your distributor for quicker but less advance and run more initial advance. Keep your tires inflated to equal pressures front and rear and at a high enough prssure that you get a full tread width on the road (normally 28-32). Run your engine at or near 180F - 200 degrees F (a 180F thermostat). Make sure your plugs and wires are in good condition. Clean air filters are necessary for good mileage. Make sure the warm air manifold and valve are in good working condition. There is more but this will get you started.
