How do you identify small block Chevy heads by the symbols on the end?

Answer 1

A rectangle, is the old 4 barrel head, junk. That same rectangle with a triangle on top of it, late model smog head, junk, again. Double humps, or camel backs, are either a 461, 461X, or, a 462. The preferred head of the sixties, and early 70's. Could be 1.94, or 2.02 intake, 1.60 exhaust, and decent sized runners, that can be ported way out. Now, the same double humps, but with alternator bracket holes, will be a 186/041, casting. Same as double humps, but more rare because of the threaded holes. Both of these castings have a small combustion chamber, for higher compression. The 441, a laterr version of the 186/041 is just that. The same, but with a larger combustion chamber, to lower compression. They have the threaded holes, but a half of a triangle. Then, there is the one with the holes, and just a point. These were never installed on any car from the factory. They are a race head. The 292 "turbo" head. 2.06 intake, and massive ports, with a small combustion chamber.