is there a way to replace or reprogram the brains for a multiport 460?? i mean, identical motors with carbs are makin more power with better economy, and i really dont have the time or money to make that switch, so whats my best option? IS a carb switch my best option?

 

Not an expert but a stock 460EFI, in good condition should easily get better milage than a stock 460 carb.
I think you should check for trouble codes. I would also check for restricted exhaust flow.

 

There are guys here getting mid teens milage with the 460/5-speed combo and lots more that manage low teens, so if you're not in that range then something is wrong and you should start by pulling the codes and making sure the motor gets a basic tunup. Codes can be pulled without a code reader but the readers aren't expensive and take all the guess work out of it,see www.fordfuelinjection.com for more info.

 

at lower speeds, such as cruising around town, it throws a misfire code, but i never hear it. at highway speeds, it doesnt throw anything. i have used fuel injector cleaner, fuel system cleaner, marvel mystery oil, sea foam, and have changed the oil, replaced the air filter, replaced the plugs and wires, and cleaned the distributor. it has summer road tires, inflated to 65 psi on the front and 80 out back. the exhaust is 2.5 inch true duals through 22" cherry bombs. the best mileage i have EVER seen out of this truck was 11. it DOES burn a little bit of oil, a result of 147,000 miles. could this be causing something unexpected that is lowering my mileage?

 

Oil consumption won't make any difference unless it's enough to foul the O2. Speaking of which you do have an O2 sensor installed and hooked up? Tires are stock size or fairly close? And the speedo has been checked for accuracy?

 

pretty sure the O2 is connected. havent checked. O.o and the tires are exact stock spec, and my speedo reads about four miles over at 70. i use a garmin nuvi to clock mileages and speeds.