ok my bro has a head that says pr3-4 on it. and he was told that it was a type r head is this true. if not what is the code for a type r head and what is the code for a b16 head. it has the b16 intake manifold on it. one of his friends recently bought a type r head and it says the same thing on it pr3-4. can anyone help me?

 

mine is a b16 head and it says PR3, i think the PR4 is the type r, but i'm not sure.