51 year old FE powered F-100 gets 20+ MPG!

[TimeWarpF100]

I was finally able to get a few things resolved with my 352 Powered 1966 F-100 Ranger.

This is a bone stock F-100 as it left the factory back in 1966!

Equipped with a 352 with 3spd OD trans and 3.25 gearing for a 2.275 final gear.

The OD unit did not work when purchased and was in dire need of a tuneup. Took a few weeks to figure out the operation of the factory OD.

I did some testing to correct speedometer to read actual for exact info.  Right now in a 81.1 mile loop I was able to get 20.77888 MPG!

I did replace the stock distributor with a new over the counter so I would have proper vacuum advance.

12 deg initial timing with 32 total plus vacuum (I might be able to tweak more to see if any further gains)

87 octane fuel

81.1 miles in a "sipping" 3.903 gallons. Filling each time so it was up to brim.

I think this is fantastic that the technology was there back in 1965-66 but so few people chose it.

This particular ranger is one of only 3 known to exist with the 3spd OD trans for 1965-66 Trucks including ALL engines.

Running 15w40 Diesel oil

Engine has never been apart all original to the truck components (except dist.)

180 deg thermostat stock radiator

Truck also has Factory Power Brakes & Power Steering

This was running the FREEZING cold Dealer installed A/C

Max speed was 65 mph with a typical cruise around 60-62 a few stops in light traffic no extended sitting times.

[BattlestarGalactic]

I agree, it was all possible back then.  I can't really say or remember what my wagon got with the 3spd OD, though it had 3.89 gears in the back.  It was 25 yrs ago. 

You are likely on very flat land.  Come to the hills and likely it won't do so well.
My '95 F100 with 3.08 gears and automatic(4rl..whatever it is).  Gets worse mileage then my previous '95 F100 that had 3.31 gears(both 302's).  The present trucks seems to like to downshift a lot on grades where the other truck could hold speed better with the couple hundred more rpm.  I thought the desert gears would be great, but it reality they suck.  I look to maybe switch them out sometime in the future.  We'll see. 

With a manual transmission my truck might do better if it didn't take the opportunity to downshift so much.  Just a touch of throttle may help but the computer determines what happens.

[TimeWarpF100]

I agree, it was all possible back then.  I can't really say or remember what my wagon got with the 3spd OD, though it had 3.89 gears in the back.  It was 25 yrs ago. 

You are likely on very flat land.  Come to the hills and likely it won't do so well.
My '95 F100 with 3.08 gears and automatic(4rl..whatever it is).  Gets worse mileage then my previous '95 F100 that had 3.31 gears(both 302's).  The present trucks seems to like to downshift a lot on grades where the other truck could hold speed better with the couple hundred more rpm.  I thought the desert gears would be great, but it reality they suck.  I look to maybe switch them out sometime in the future.  We'll see. 

With a manual transmission my truck might do better if it didn't take the opportunity to downshift so much.  Just a touch of throttle may help but the computer determines what happens.

40 mile each way loop. Lots of inclines but nothing STEEP. From my place to airport its about a 1000' change in elevation. I was quite surprised that on the hills it did so well. Testament to the low RPM of the 352. Top RPM was 2000 in cruise mode went up to 3000 rpm once in 2nd gear. I really expected it to go into Passing gear/ kickdown on the hills but it did not even feel them in High OD.

My dad bought a new 1966 F100 back in october 1965 it got 10 mpg but was a 3spd column shift with 4.11 gearing. I really did not expect this truck to do what it did power wise with a 2.275 final gear.  Have another '66 352 with 3.50 gears and 3spd but it has a different kinda lumpy cam. Killed the MPG

[machoneman]

I'm more amazed the thing doesn't smoke at ton from old, dried-up valve seals!

Yes, tweak your vac. advance as much as the combo can stand....for better fuel mileage. However, if your going to do heavy haulin' (in the back or a trailer) take that advice carefully!

[Pentroof]

Is that all?  I would have guessed 20.77889 mpg, minimum.

Nice to see some original stuff still around.

[TorinoBP88]

Sweet, the 352 is such a great smooth runner. California had will almost always her 10 percent less.

Give is an update after 1000 miles.

[TimeWarpF100]

I'm more amazed the thing doesn't smoke at ton from old, dried-up valve seals!

Yes, tweak your vac. advance as much as the combo can stand....for better fuel mileage. However, if your going to do heavy haulin' (in the back or a trailer) take that advice carefully!

Not even a puff of smoke. Runs so smooth and so well.
With stock muffler it's so quiet too.

Seems funny to have a 51+ yr old truck with stock drivetrain turn under
2000 rpm @ 70mph. MPG & FE usually not used in same sentence   

[TimeWarpF100]

Sweet, the 352 is such a great smooth runner. California had will almost always her 10 percent less.

Give is an update after 1000 miles.

Just had minor surgery this morning so could be out
For a bit. Will tweak n test more when I can.
Filling to brim before and after on same pump and knowing
Odometer is spot on not expecting much diff results. Other than will
Not need A/C as weather has cooled. This I prior to vacuum advance
Hooked up.

[TimeWarpF100]

[chris401]

Are your heads C6TE-G? The 66 Galaxie engine in my truck had the underilled casting.

[TimeWarpF100]

Are your heads C6TE-G? The 66 Galaxie engine in my truck had the underilled casting.

I have had 1/2 dozen '66 truck 352's. All C6AE-R

[chris401]

Are your heads C6TE-G? The 66 Galaxie engine in my truck had the underilled casting.

I have had 1/2 dozen '66 truck 352's. All C6AE-R

Yes, C6AE-R is the most common head.