272 to 312 Swap?

[Anteek29]

Have a '55 Fairlane with a stock 272 & Fordomatic. Will a stock 312 bolt up OK with this trans without modifications?

[dmsfrr]

If the '55 272 is original...
the 2bbl carb, distributor and intake manifold may be specific to that year only.
Exhaust manifolds were upgraded / enlarged in '57.
Using the '57+ versions of those parts is a definite upgrade and will compliment the performance potential of a 312.
An oem '55 Fordomatic behind a 272 would be the air-cooled version.
Ford upgraded the FoM in '56 to a fluid cooled version for the higher HP 292's & 312's.

Is the Fairlane still 6volt, or 12v? The ignition & coil wiring is different.
'55, '56 and '57+ use different water temp sensors that don't interchange.

.

[Charlie Stephens]

If the 312 came from a bird you will have a few parts to swap over from the 272. Front timing cover comes to mind.

Charlie Stephens

[dmsfrr]

Originally Posted by Charlie Stephens

If the 312 came from a bird you will have a few parts to swap over from the 272. Front timing cover comes to mind.

and...
oil pan, dipstick & tube, water pump spacer, crankshaft pulley, timing pointer, driver side exh manif ...

[BW]

I think the radiator is different for the 312, But the 272 one will work

[Y-Blockhead]

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Originally Posted by Charlie Stephens

If the 312 came from a bird you will have a few parts to swap over from the 272. Front timing cover comes to mind.

Charlie Stephens

You can keep the T-Bird timing chain cover if you are not using the steady rest. (Does anybody still use the steady rest??)

You may have to change the throttle/kick down linkage if your 272 has a two barrel (More than likely does have a Holley/Ford 94 series) and the 312 has a 4v.

[cudaboy]

id love to find and build up a 312 are they quite rare?

[Dobie Gillis]

Originally Posted by cudaboy

id love to find and build up a 312 are they quite rare?

The 312 had lower production numbers than the 272 and 292 so these days they're not as easy to find. A lot of them died of cracks in the main bearing webs because, early on at least, there wasn't enough meat there to accommodate the larger diameter of the 312 crank reliably. Ford addressed that issue in later production. A 272 or or 292 can be made into a 312 by offset grinding the crank to produce the 312 stroke and using 312 rods and pistons. Or by turning a 312 crank's mains to fit the 272/292 bearing webs. That way you have a better 312 than the factory made because the main bearing webs are beefier. If you go shopping for a 312 it's best to keep in mind that all y-blocks for sale are 312s. The proof of the pudding is the aspirin sized dot on the rear crank flange and measuring bore and stroke if possible. Caveat emptor...

[dmsfrr]

Originally Posted by Dobie Gillis

If you go shopping for a 312 it's best to keep in mind that all y-blocks for sale are 312s. The proof of the pudding is the aspirin sized dot on the rear crank flange and measuring bore and stroke if possible. Caveat emptor...

An oem 312 engine also has "ECZ" cast into the main bearing caps.

"Caveat emptor"
Times 2
just today on ebay I've seen almost a dozen y-block heads, blocks, etc. being advertised as something they aren't.
'54 256 only heads being sold as fitting newer 292/312
272 engines listed as 292's
'55 or '56 only parts labeled as '57+

And if it isn't being called a "312", parts are often listed as fitting a particular model when they don't.

.
.

[Anteek29]

Thanks for all your informational inputs, guys! I've learned a few tidbits.

[Daves55Sedan]

To answer your question, the 312 engine will bolt up to a Ford-O-Matic that was used with a 272 or 292 V8. these all had the 12" converter. The 215 and 223 I-block 6 cyl used an 11" converter and had a smaller bellhousing.
Actually the air-cooled converter was discontinued in Late '56 for the '57 model changeover. All '57 cars with V8 had the new water-cooled converter. The air-cooled converter was still used with 6-cyl engines all through the 1950's as a water-cooled version was never produced for the 6-cyls at least through '59, maybe later.
Yes, I do still use my front engine steady-rest on my 272 and on my 223 engines. Do you mean people are leaving these off?
dmsfrr is right. You can't trust anything you read on e-bay as far as what they claim parts are for.

[Daves55Sedan]

Tell ya what, if you run across a machinist who builds engines and is known to be meticulous and detail oriented, you can give him an old 292 truck engine and he can turn it into a screamer that'll put a 312 to shame.
292's are more common as they were used in Galaxies thru '62 and in pickups thru '64. 312's are much much harder to find.

[Ole Don]

Yes, I left the steady rest off the 312 in my 55 sedan. I bought new motor mounts, then did this. I drilled two 5/16 holes in each one, then put in new 5/16 grade eight bolts. I did not tighten the nuts all the way to give the MM room to move like they should, but double nutted them. Used them like that for years, some drag racing, lots of miles.

[Alaska Jim]

excuse me, but I am unsure what the "steady rest" is can you enlighten me? been away from Y-Blocks for many years until about 1 1/2 years ago , got back into them when I was offered some a fella was going to scrap out, and I saved them for future projects.

[Daves55Sedan]

Originally Posted by Alaska Jim

excuse me, but I am unsure what the "steady rest" is can you enlighten me?

The "steady-rest" is a third motor mount located at the very front of the engine. It is a funny horseshoe shaped contraption that bolts to the front of the engine block and is fastened to a heavy "tab" at the backside of the front frame crossmember with a cast spacerblock and thick rectangular rubber blocks above and below the frame "tab".
Basically, the "steady-rest" prevents the engine from tilting backward if ever the transmission is removed.
Ford designed the "power plant" with FOUR mounts; one on each side of engine, the front steady-rest and the transmission crossmember mount. The support system, if you can envision drawing a line betwwen these four points, resembles a "diamond" pattern.

[Y-Blockhead]

Originally Posted by Daves55Sedan

Basically, the "steady-rest" prevents the engine from tilting backward if ever the transmission is removed.

Haha, that's a good one. You will notice Ford discontinued installing the steady rest around 1957/58.

[dmsfrr]

Originally Posted by Daves55Sedan

The "steady-rest" is a third motor mount located at the very front of the engine. It is a funny horseshoe shaped contraption that bolts to the front of the engine block and is fastened to a heavy "tab" at the backside of the front frame crossmember ...

Looks kind of like this one?

[dmsfrr]

Not to be confused with the steady rests in a '55 / '57 T-Bird.
A pair of rubber bushed rods, one from each side of the engine block to the frame.
To prevent the engine from rocking side to side, since the two main motor mounts are both at the center-line. One each below the crank damper pulley and transmission, making a very top-heavy assembly.

[Daves55Sedan]

Originally Posted by dmsfrr

Looks kind of like this one?

Yes, that is the steady rest for the '55 & '56 272 and 292V8 engines installed in full size car & wagon models.

Yes, the T-Bird steady rest is different due to the differences in car frame.

Yes, the steady rest was eliminated on 1957 and later models.

[Alaska Jim]

o.k. , thanks guy's I have a couple of those laying around, and just did not know the proper name. I just referred to them as a front eng. mount. thanks for educating me. ---- Jim