What ZC Engine Do I Have?
 

I bought a '91 hatch, the owner told me the engine was swapped out. He didnt know anything about the engine mainly cuz he bought it with the swap already in it.
I spent countless hrs looking for info but no real luck.
all i know is the block is stamped with [ZC 5756460].
My questions: Are parts hard to find, what are the specs, and is this engine worth tuning?

Just hearing "ZC" makes me automatically think it will be difficult to find aftermarket parts for it. I could be dead wrong though. Are there any dates stamped into the head that you can see?

The only other Stamping i can locate is one near the headers, is (PM3-4).
If this helps with identifying the engine