Ford 223 "Mileage Maker" gas mileage

[ThinLizzy13]

So I recently drove my 63 on a bit of a road trip and was flabbergasted by the mileage I got after putting a new Autolite 1101 on. My 63 F100 is essentially as it was in 1963 except for a three things...

- Radial tires instead of bias ply
- The generator has been converted to alternator
- Engine is bored .030 making the 223 a 227ish (Roughly 15k on the rebuild)

Now everything else is as it came. The notorious Load-o-matic setup, strong arm steering, no power brakes, points, etc; My old Autolite had leaky throttle shafts making it almost impossible to tune in correctly. My mileage before the carb change was about 14ish at 55mph, which I felt seemed low for Ford's "economy" engine. I thought 16 should be attainable at that speed on flat ground (I lived near the beach. Everything was flat.)

My first drive after the swap was a truck load from SC to NY, all highway, at about 65 MPH the whole way.



I almost couldn't believe my mileage after getting a good Autolite on there....I got 15.8, 17.3, 17.1, 18, and 17.9! I thought after my first two fill ups that I had somehow made a mistake

I'm excited to see what mileage I'll get without a load on highway, or around town, or what it might be after a DSII/Carter YF swap!

[slick4x4]

I was getting 13-14 on long trips with my f100 4x4
Low gears & not quite as aerodynamic

Fred told me his 223 was getting 20 mpg @ 70 mph
He installed the overdrive transmission
It was a f100 2wd with a topper

[bobenhotep]

I swapped out the 223 for a 300, and on my trip to Slick Stock and back, even with mountains and high altitude I averaged 18.5 mpg after all was said and done. With the 223 and the right gears you can get good mileage. Fred (the guy Pat is talking about above) had a 223 with a t-5 behind it, and at one time was getting around 23 mpg on highway.

Dan

[64 f100]

Back in the 60's, I borrowed a friends fairly new 65 long bed f100 with 352 and stick and overdrive which got around 15mpg. Thought I would mention this for comparison. The 223 was known for decent mileage if kept up, which was a questionable item for many of the trucks. I believe carbs were sometime not in good condition and gave problems. These engines were often ran without valve adjustment which were required maintenance if I remember right. Also, many of these engines were ran long past the point of being worn out or needing a head rebuilt. The 300 was one of Fords best with one exception, but this was not the engines fault. People would replace the water pump and fail to install the short bolt in the right place and instead install a long bolt in the wrong place, which would go in to far and crack the cylinder wall. Ford installed slightly smaller pistons in some early 80's 300 engine which caused engine slap on some of these engines once the engine got some wear. I had one that nearly sounded like a main bearing knock. Finally got to the point that when I pulled up to a stop light after running it hard smoke would come out from under the hood. I don't remember how many miles this engine had on it when I finally pulled it and replaced it with a healthy 302.

[ThinLizzy13]

I was getting 13-14 on long trips with my f100 4x4
Low gears & not quite as aerodynamic

That seems decent for a 4x4. I think I’m running 3.92 gears in mine...

Bobenhotep - that’s pretty good mileage! 300’s are great. If my 223 wasn’t practically “new” I’d be dropping one in.

Sounds like Fred has a nice setup. I was looking at pic’s of his truck recently with the cap because I would also like to put one on my unibody. Looks like I might copy him with the overdrive too.

64 F100 - I would love to be able to get 15mpg out of a 352. It’s definitely true that if you don’t stay on top of the maintenance with these old engines that performance drops noticeably.
Did not know that about the early 80’s 300s. I knew they changed the timing gears to phenolic. I ended up with an 80’s engine in my old F250 and it definitely had a different sound to it...

[BarnieTrk]

I think I’m running 3.92 gears in mine...

17-18 mpg @ 65mph with that tarped load..... that's pretty good in my book!

The radial tires will reduce the rolling resistance some, but those big western mirrors don't make it real 'slippery in the wind'.

BarnieTrk

[Jason_S]

My first drive after the swap was a truck load from SC to NY, all highway, at about 65 MPH the whole way.

Quite a road trip. Unloaded ought to bring on even a little better mileage.


Before the 55 mph speed limit changed in the 1990's, I was able to get 20 mph a few times highway driving with the 223 in my '64 and 3.89 gears. However, I think most of those times were in the winter with the windows rolled up.

I wouldn't try to drive those same highways with the truck today. Posted speed limit now is 75 mph and traffic is usually pushing 80 or more.

[The Big M]

Very nice ThinLizzy, thanks for sharing your results. What's your axle ratio?

[ThinLizzy13]

Very nice ThinLizzy, thanks for sharing your results. What's your axle ratio?

I forget which one, but it is either 3.92 or 3.89