I have a 300 straight six, headers, Offenhauser DP intake and Edelbrock 1403 (500 CFM). I kept it at 55 mph on a trip to Houston one time and managed to hit 18 mpg.

 

I have a 1969 360 2100 carb. that gets about 12 , thinking of replacing the intake and carb to a 4 barrel 500 cfm in hopes of getting 1.5 to 2 more .....anyone know if it is worth the money and effort ?

 

Uncork what is already there with headers and a free-flowing dual exhaust system before upgrading the induction side of the engine.

 

that is in process , putting headers , clutch fan, pertronics, plugs wires and have rebuilt the carb . It runs GREAT and I love it , just trying to save a little gas from a truck that is addicted to it !! haha...and for the record I'll buy gas for my stump puller and know it will never be an economy truck just wondered if replacing the intake and carb was worth it ?

 

79 F150 4x4
400 holly intake, cam, headers, 2.5" dual exhaust out the back, MSD ignition box and coil, 650 eldelbrock carb with vacuum secondary.
NP205/NP435
35" BFG A/T tires
4.56 gears with a Detroit in the rear
93 octane gas so it doesn't have detonation

Driving it around town and the on Kentucky backroads I averaged 12MPG. Now that's also with me keeping my foot out of it and not going over 55. Since the 98 2wd I had only got 15, Im pretty stoked!

 

460/ 4.11/ C6/ Holley QJ 1406 (Gone and good riddance)

I'll report on the new 4bbl (Edelbrock) and the CJ intake.




Dunno the tire size. Not big, not aggressive.

 

79 F250 std cab lg box 4x4, mild 400ci, T18 NP205, D60, 3.55 gear, 37" bfg's - 12mpg best/10mpg avg around town - mustang chassis dyno at 240rwhp/355rwtq

79 F250 CC 4x4, mild 460, t18, NP205, D60, 4.88 gear, 40" toyo's - 8.25mpg @ 65-70mph highway...going to do a tune-up and report back next spring with around town mileage and dyno numbers


BTW - both speedometers verify'd with construction radar indicators for true mileage

 

400M, .040 over. Stock otherwise. Downhill with a tail wind I get about 12 mpg. Normal driving it's around 10.

 

74 f100 390 670 truck avenger np435 205 410s on 37s I pull an extremely steady 7mpg. City flat roads free way up hill down hill hauling a trailer towing farm equipment or just empty it gets 7

 

1975 f250 Super Cab 2WD
460, bored. 030 over.
Ported D3VE heads.
Edelbrock 1406
Edelbrock performer 460 intake.
Recurved dist with adjustable vac adv. Timing at 16*
Hedman headers thru dual Magnaflow. No cross pipes.
3.54 Dana 60 with LSD.
C6 trans.
Truck runs 200* any time, any season.

6.5 MPG... always.

 

'78 F250 4wd, 400, C6, 4.10's. Pretty much stock & low miles. The couple of times I have measured it: high single digits in mixed driving. Mostly I use it when I need a truck and fill when empty.

Might I modify it in the future for more mileage (and power)? Yes. Higher CR and quench and a 4 bbl or EFI + headers might get me a bit more mileage (10-20%?) and put me in the low double digits. I won't loose the 4.10 as I tow time to time and OD in these rigs does not seem practical, especially with 4wd. I might try a front air dam from a newer truck also for the Aero.

 

1973 F250 Camper Special. Currently daily driver
Stock 390 2bbl, C6 trans
Stock everything else as far as I know
No AC pulley to put extra drag on the engine
7½-8 mpg if I am gentle with the gas on my short commute, better on freeway, maybe 8½-9 mpg
But I've got a long LONG way to go on a rolling restoration

 

I pay &.40-$.45 per mile, to drive my truck.

 

'75 360 stock 2BBL auto, 2wd, 31 10.50 BFGs I get 12-14.

My '86 Grand Wagoneer with the AMC 360 stock, 2BBL, 4x4 auto 32s 7.65 YIKES!!!