Improving MPG
LOL, sad but could be true!
Reasons why I have a locking gas cap...
Whats your tire pressure?
Are any brake dragging?
Hows those wheel bearings up front? Plenty o' grease? Not too tight?
Adjust the valve lash .010" intake .020" exhaust.
Hows the air filter?
Is the transmission in good working order?
Is the differential lube topped off? Any noises back there?
What car is it? Is the engine stock?
Does your gas have any ethanol in it?
EDIT: also, what plugs are you running? Is it a reman carb? What temperature thermostat are you running?