292 Turbo Heads
The 292 "turbo" head was the first generation, over the counter racing head offered by Chevrolet for the small block. This is a very good cylinder head, but generally needs to be ported to serioulsly out-flow a comparable "double hump" type head.
So, the answer to your question is this, if you've got stock type open chamber heads now, the 292 turbo heads will give you a performance increase, if you are capable of doing some good pocket porting, they are easy to get some big air out of them.
A little outdated, but still a good head.