I have a B18 and on the block it has a series of numbers, what do they indicate? Any idea what these mean?
What do the numbers under the engine type indicate?
a thousand times thank you for your help and any information!!

 

P72-2 is the head stamping... means it's a later model P72 head. The little circle stampings in that same picture indicate manufacture date. 0/0 means made in 2000. Not sure about the other circles.

In the second picture B18C1 is the engine designation. The numbers below that I believe are a serial number that can be traced back to the VIN of the original vehicle it was installed in.

 

On the cylinder head in the first pic, the "00" in the first circle on the left indicates the year of manufacturer, and the "08" in the second circle indicates the month of manufacturer. So, the cylinder head was created in August of 2000. Now, in the lower picture, the 7 digit serial code begins with the number "8" (the one on the LEFT) which suggests the engine is in fact a 2001 GSR engine.