World Products S/R cylinder head, part number 042650, has recently been added to the NHRA accepted products list for Small Block Chevrolet engines in NHRA Super Stock. The World head is a bolt on replacement for factory heads and offers a far more robust and durable casting than the notoriously crack-prone stock pieces.
The S/R cylinder head offers a highly efficient 58cc combustion chamber and 170 cc intake runners. This head with its compact chamber is ideally configured for 305 cubic inch engines. Cast and machined in the USA with special high-density iron alloy for superior strength, the S/R head has extra-thick decks and screw in rocker studs for added durability in highly stressed racing applications.
World Products NHRA Super Stock legal cylinder heads:
Part# Intk Port Chamber
042650-NHRA 170cc 58cc
043600-NHRA 170cc 76cc
043610-NHRA 170cc 67cc
World Products cylinder heads are made in the USA using a state of the art foundry and ISO 9000 certified machining facilities and practices.
This story was originally published on May 28, 2015. 
