I just bought a 1978 F150 LWB w/ 460 4 barrel carb. What kind of mileage can i look for???
Wife thinks I will only get about 8 at the most. i am thinking more like 12.

 

Yeah, your looking at about 8. My 1979 F150, 351m, c6, 2wd, 3.5:1 rear end, gets about 8 city, 12-13 highway.

 

Yup, thats about what your looking at. My 1977 F150, 300 I6, C4, 2wd, 2.75:1 rear gets 19.5 all day long, with a stock 1 bbl, and stock exhaust.

PS: Welcome to the forum

 

I have had three 460 powered trucks. An 81 f100, 2wd w/460 & auto, 3.00:1 gears getting 14+ mpg. A 79 f350, 4wd 4spd, 4.11:1 gears getting 8+ mpg. And currently have a 96 f250, 4wd auto w/OD, 4.11:1 gears and 8- mpg. My brother and I did the conversions on the 81 and 79 as well as built both engines. The engines were mostly stock with a mild towing RV style cam grind. All tire sizes were close to stock and the speedo's within about a MPH known accurate one. To be fair, in addition to the gears, the 81 was a SWB light duty truck and weighed about a ton less than the others.

 

my '79 with 4.10's gets about 10mpg at 65mph unloaded (i don't drive any faster than 65 with it)

with a trailer at 60-65 it will get about 7.5mpg
with a heavy load at 55-60 it got about 6.3.mpg

look back through the threads, there was one about mileage when towing and there was a lot of feed back in that thread.

a search for my user name would probably find it, if you like.

sounds like gears can make quite a difference.

enjoy!