This car is for sale and claims it is a 312 engine, but several things make me question that.  The heads have sand core plugs/freeze plugs in the ends, an aftermarket intake manifold and carburetor, and headers.  I was under the impression the freeze plugs were pre-56, which would preclude this being a true 312.  Is that correct?  I went to Mummert's site and I  have printed off the block numbers, head numbers, crank identifying dot, etc., but if this is bogus, then the price is way too much for this car.  Any ideas would be appreciated.  Thanks, Joe-JDC

JDC

The heads are not original for a '56.  Most likely, the engine has been swapped.  What  should be in the car, according to the VIN?


Lawrenceville, GA

Depending on location 56 Canadian heads had the frost plugs in heads.I have a couple "C" heads with plugs and a friend with "H" heads with plugs.

Joe JDC.  OlWeldinrig and Carl are correct.  EARLY '56 FoMoCo y-block heads had the 'freeze plugs' or 'soft plugs' like those used on '55 vintage y-block cylinder heads.

I got tripped up on the early '56 cylinder head bit, also, in an earlier posting.  Paul2748 in Midland Park, N.J. set the record straight for me and who I was writing to at that time.  Getting information right is what all of us want and need.  IF this is the biggest error Charlie has ever made, he's way ahead of me and many others of us here.   

Joe, I share your skepticism that the '56 you're looking at has a 312 in it.  Most '56 312s were installed in Mercurys and T'-Birds.  Some '56 Fords did have 312s, but many more came equipped with 292s or 272s.  Like you, checking the crank flange or the casting numbers on the main caps between the two hold down bolts is the best way to know for sure.  As you likely know, the 272 and 292 main caps are marked EBU while the 312 main caps are marked ECZ.

Hope this helps!  


NoShortcuts
a.k.a. Charlie Brown
near Syracuse, New York

Not to steal this thread, but the freeze plug in the head is new to me. I've been away from Y-blocks and into flatheads for several years and there is much more support and info about them now as compared to then so I'm still learning. The heads in my '55 have no freeze plugs on the front face of them. Does that mean that they are later heads? Any info to identify them while on the motor is appreciated. I was told by the seller that it is a 272" and it has ECG casting behind the valley pan/next to the distributor.

 EDIT: I should have Googled it first. I found a site listing casting location and numbers. These heads have ECZ-C on them and could be from 7.6 CR to 9.0. I suspect the former. 

The serial # indicates what it was originally. As I recall P indicates 312. My first wife had a nice '56 Vicky that was a 312 car. The car was much nicer than she was. She's long gone as is the Vicky. Wish I still had the Vicky glad the wife is long gone. To me the car is worth more with the P serial #. The 312 can be replaced. Can't change the serial # and the fact that it's an original 312 car.  312's are less common but there were a lot out there. Know of at least a half dozen in my small town back in the day.

Joe.  You might want to check the casting numbers on the heads.  ECZ-C heads were supplied with and without the end core plugs in 1956.  I’ve even come across an unmolested 1956 engine that had one of each.  As a general rule all 1955 heads had core plugs in their ends but the change to non-core plug heads occurred during the 1956 model year run.  It’s still possible to have a 312 bottom end with the top end being off of a different Y.
 
As far as identifying the short-block as a 312, the casting numbers on the block will help but those numbers are not definitive as some of the 292’s shared the same casting numbers as the 312’s.  The 5/16” dot on the flywheel flange is very good indicator of the crankshaft being a 312 but be aware that there are 312’s out there that have no dot on the flywheel flange.  And then there are the 312 cranks that are in 292 blocks with just a minor amount of machine work.  Even checking the bore size is not definitive as any 292 bored to 3.800” or more can be confused with a 312 bore size.  The ‘ECZ’ on the main caps is the best identifier for the block itself being a 312.

Lorena, Texas (South of Waco)

I was curious to how to read the date codes on the heads.It is likely very easy but does anyone have this info?
Dave