On a 318 you can get all the head you need with some cleaned up iron heads. Regardless of the part number they are all basically the same with a little porting.
Iron makes more power than aluminum because it keeps more heat, and heat is power. This is not to say you can't buy aluminum heads, but for that size of engine you can do a lot with
Oh no! Here come the debates!!!! You’re wrong, I’m right. No! You’re wrong I’m right. You have no idea! No! YOU have no idea!
Aluminum!
Cast iron!
Aluminum!
Cast Iron!
Aluminum!
Cast Iron!
