Can anyone identify these heads?

The oddball 915 j 'smog head' or not..
They're an oddball...with their one digit short of the famous 915... to their smog era exhaust port floor injection bosses. They can be found all the way into 79 or so, who knows really. As far as I can tell..they can be found in vans,trucks. They must have been introduced sometime around '74 or later? I'm really guessing..however...they look like a j intake port but have a smaller late 70's model exhaust port.
Just what I know about them.