I picked up a 455 motor recently with a 69 block "M coded". Curious what it may have come out of. Has a 2 barrel intake and CA heads. Wondered if CA heads are any good, or look for a different pair for my rebuild. I can't seem to find much info out there on the heads.

 

It could have come out of any D88, D98, or Toro built in 1969. Assuming the 2bbl manifold is original, it's likely a 9.0:1 D88 motor. CA heads are virtually identical to C heads. Perfectly good heads to start with.