The term "Brick" refers to the aerodynamics. However, I actually think a brick is more aerodynamic than these old trucks.......

 

i'm not disagreeing with the air-flow theory here...i've just never met anyone who had a 4-barrel who could keep their foot out of it. me included.

 

I've probably owned and driven as many of these old trucks as any of you and I never referred to them as a brick. Barn door was more like it,lol. And yeah, they will run, that's not the issue. My tired old 69 with a stock 390 2 bbl and 3.73 gear would still bury the peg. The best way to get better mileage is just slow down. Most of them will get at least 2 mpg better at 60 than they do at 75.

 

Amen brother

 

2nd that !!

 

I shoe horned a 1977 400m into my 1968, with a c6 behind it. Im getting close to 17 mpg on highway and staying close to that on the surface streets. Im fixin to pop a 4bbl on it and get rid of that gas drinking 2bbl. I had no luck getting any gas mileage out of the original 352 in my first 68.

 

Mike bet you have a mis-matched speedo gear with your rear end ratio. I know you don't want to hear this, but your truck is not getting 17mpg. Your speedo is probably 10 or more mph off giving you a incorrect reading. These old trucks might get 10-12 if pedaled softly, but that's about it.

FYI: Your 68 would have had a 360 in it. The 352 on the front of the block was a foundry mark. The 390s had it also.



John

 

Just bite the bullit and get a 4BT Cummins, should easily get 20+. I hear claims of 25-28 in 90s F150s.

 

i have never liked the "brick" comments either and it seems with all the other rounded edges it shouldn't be that bad but i have always wanted to see one of these trucks in a wind tunnel and i have yet to own an FE i didn't like even my 352 i had in smokenchoke and then my 72 gets 14-16 mpg all day long plenty of power and would do 110 mph till you get tired of it and even going that fast it get's 8 mpg (still better than my old 1/2 ton chity's 350 doing less than the speed limit) ..... and for bricks my 66 goes so fast i don't even have the ***** to top it out yet till i get some better tires and drive shaft rebalanced i have put 2.78 gear rearend in it where it had a 4.10 before so now speedo says 42-44 when my gps says its doing 65mph and i have wrapped it up to 90 mph on speedo and about crapped my pants because of vibration and still had go pedal left ..... i miss Red Dawg (78 f150 460) it would set at 120 and cruise and would pop up to 140 but that is besides the point sorry for getting off topic.......... 360's tend to get crappier fuel mileage 10-14 due to low compression they have the exact same stroke as the 352 and same bore as a 390 on paper they should be amazing but they aren't due to compression but they are dead dog reliable and last forever ...... 352 will yield slightly better gas mileage 14-16 with similar power and will bolt in your application perfectly..... 302s are nice and have good fuel mileage in bumpsides we used to get 14-18 for years..... it is all in gearing timing and good exhaust on an FE sorry again for the rant