I have a tired and weak 312 motor in by 57 Bird. A "Ford Guy" near me has a 1956 Merc 312 available is very good condition. How easy of a swap would this be, I know I need to use my distributor w/tach drive and I think my Holley carb. Anything else that might need changed or swapped. BTW, the engine in the car is not the original engine that the car was born with so the motor exchange is not a big deal. 

1957 Thunderbird 312 Fordomatic

Pretty easy. Just off the top, the dizzy, oil pan with tube, front motor mount, balancer, and maybe the timing cover.

Might check the head numbers, I used a 56 Merc 312 for my roadster, and it didn't have as good a head on it as a 57 bird would. Same with the intake. But who knows what's there till you check.

You might take a look at J Mummerts site, on how to ID a 312, since all used Y blocks are now 312's.

http://www.ford-y-block.com/technical.htm

miker
55 bird, 32 cabrio F code
Kent, WA
Tucson, AZ

you will need the 57 intake manifold to the 57 carb. and the Dist. to match. possibly exh.  manifolds , not sure about them.

Hmmmmm...

- 'Bird valley pan with its breather tube is different than the '56 Merc...
- remove the '56 Merc driver's side crankcase vent and install the 'Bird block-off cover...
- change the timing chain cover unless the Merc has a front motor mount (DUH! I can't remember)...
- transfer the 'Bird front motor mount and timing chain cover ignition timing pointer...
- swap the crankshaft front vibration damper, 'Bird unit is unique to '55-'57 'Bird...
- remove the Merc engine side motor mounts;  replace with the 'Bird engine support brackets and accompanying support rods (check your brackets for cracks, especially the driver's side one, common problem)...
- exhaust manifolds ('56 Merc are different than the '57 Bird in size and part numbers;  driver's side Merc header will not connect with exhaust head pipe, different stud orientation as I recall)...
- swap intake manifolds ('56 Merc has a carb base for the Holley 4000 and '56 Carter WCFB carburetor base; D code 'Bird takes the Holley 4150 series carb)...
- swap engine oil pans and oil pump pick-up tubes, 'Bird is rear sump, Merc is front sump...
- oil pumps may be different, most '56 are gear type, '57 were rotor type;  either will work okay...
- swap generators and all related bracketry... '56 passenger car is different...
- transfer 'Bird water pump spacer to timing chain cover, pulleys will not align otherwise...
- transfer 'Bird radiator fan, spacer for the fan, and the water pump pulley ( I'm pretty sure that everything 'Bird is different here)...
- IF you have power steering on the 'Bird, transfer all of the mounting bracketry...
- install the 'Bird oil pan dipstick and tube, they mount on the side of the block;  make sure you plug the original 'Merc dipstick tube opening

Oh... there's got to be something else.  It's been too long and, even if it wasn't, I'd forget something!  

Put the engines side-by-side when you go to do it.  It's easier than reading this list makes it sound.

Hope this helps. 

Addendum:  I JUST read Miker's list.  Yes!  The '56 Merc probably has (?) 'C' heads (I think).  Seems like they used one head for the '56 Mercs with automatic trans and another for those with 3 speeds or 3 speeds with O/D.  Be sure to transfer the '57 'Bird large letter ECZ-G heads if your 'Bird has them 


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