I have an idea how the crack got there.  if along the way someone pts too long a bolt in the side stabilizer it can crack the block in that spot.

Mike, still lovin his 57 t'bird after 53 years!

thanks for the replies. I will update soon with next move. One option is to sell the 56 bird with all my stuff and buy a 54 mainline business coupe for sale locally. I do have to boys to tag along on rides with me along with the wife.

Thanks for the replies. Wil

I just had the same experience with a 272. I was having it bored out to 292 and when the machinist was surfacing the deck he found a crack on the r side just behind the bolt holes for the motor mounts. He sent me to a good welding shop and they welded up the crack. I wont know until next year when I finish up and get it installed in the car if it was successful or not. Anyone else run into this w/success?

Dan      Kingman Az.      86409

How bad is the crack? Possibly the engine came from a wreck?. If the crack is only on the outside, possibly it can be stitched or welded? Or go with the 292, or have the 312 crank mains & seal area turned down to 292 dimensions. The specs are available at John Mummert's site in the links. Probably shoulds avoid the 239 block as there are interchange problems with later blocks & parts.

Paul

Machine shop says my 312 has a crack at the motor mount. Cylinder walls are standard with some decent rust. I thinking of using my 292 for my build. I do have 312 rods and what I believe to be a 312 crank. Should I pursue the 312. I also have the rotating assembly for the 292 along with a 239 long block.