Gemsa cast his 'banger heads with a large opening at the back. "This was their version of the freeze plug," Max Jr. explained. "Instead of running freeze plugs like you see in heads today, he cast them wide open. The open end was sealed up with a plate." You can see the plate at the upper right in this photo. H&H set up the cooling system to run water into the engine from a port on the driver side of the block, where the lower neck is located. A braided line delivers cool water into the back of the head.