i understand a b16 head is stamped pr3 but i just read that "Let me give you a heads up. The P72 (gsr gead) and P73 head (B16 and type R)" from this forum "http://forums.beyond.ca/showthread.php?threadid=55289"

i dont understand what how b16 heads can be stamped both pr3 and p73

also what does the 4th digit mean like pr3-(1,2,3,4,)?

 

B16, B17, and ITR heads are stamped PR3-x (where x=1,2,3,4). GSR heads are stamped P72.

Not too sure what x means, but they are all the same.

 

All the stamp mean is which machine made the head, i have a friend down the road with a 00 jdm itr swap and the head is a pr3 casting. There is a set of digits in the front which indicate year, its a kind of circle with a line going through it with 2 numbers, for example, 0/0 in the first circle indicates a 2000 year head, and a 9/4 would indicate a 1994 head. This circle is located above the 4th cylinder nearest the bell housing on the front of the head, easily defined with a flash light.

As far as the PR3-2 thing, I asked a honda technician about this and his words were for a specific application, say for example that the PR3-2 heads are for the b16a3 del sol vtec block. He says this code is used so that when the deal orders a new head assembly from the manufacturer, that is has the correct parts for a del sol vtec, and so forth.

 

i have a type r head off a 2001 type R. It says pr3-4. I think 4 means the last of b16 heads that came out.