14 MPG would be the upper end of my guesstimate.....probably closer to 12.

A 351M isn't the most fuel efficient beastie Ford ever built.

 

What are you going to do if it works out to be 13.5 ?? lol its a big V-8 in a truck.

 

And the OP has gone ninja.....POOF!

 

that was weird... where'd my post go?

I wouldn't be too happy if it was 12... that's why I'm here, trying to find out if 15 is reasonable to expect or not

 

I would guestimate between 12 and 14 mpg.

But tjat is bases off of the 351W that was in my 93 Lightning and my brothers Bronco.

Not exactly comparing apples to apples.

 

I drove the '79 F150 I have daily for a while, after a fresh rebuild I managed around 11-12 on average.

 

buddy has a bronco with a 351M and a Holley 2-brl and it gets 14 in town...of coarse i tweaked it for him..

mpg can be had...tune the ignition and the fuel and run a 160-180 t-stat

 

Im pretty sure mine is around 8gallons to the foot. No i would guess about 8-12 city or highway.

 

yep this, and if its in a 1 ton expect closer to 6 all the time. They are terrible on gas, have no power, but there dependable. We have a 81 1 ton that was bought new, and its still going.

 

I'll say, I had a 400 in an 83 F150, basically the 351's big brother. Did a great job moving that truck, would pass anything but a gas station. Didn't like too many R's though. Much past 4500, kiss the bottom end goodbye.