Block usage for early 11C L78 69 camaro
 

Im restoring a 11C 69 L78 assembly date 1116 Jh per POP . My plan is to build a a open chamber L78 with 074 heads for now while i search for the born with block, it a long shot but its a local car and still hopefull i can find it. My question is would it be a 440 or 272 casting? Thanks for your help , id at least like to put the rite casting back in. Nuge. O,i do know their wasnt any open chamber l78’s , i just have a nice set of 074’s and thought id use them.

I was curious also, so I buzzed through our db.

Latest build date for a 440 block is October 17, latest cast date G168.

Earliest build date for a 272 block is September 17, earliest casting date H18.

With an 1116 build date, the OE block in your car is virtually certain to be a 272.

Open Chamber L78...
 

You will not have the L78 11 to 1 compression with those heads...not sure if they make an open chamber compatible piston for that setup?

Good luck...