GM Performance 12480129 - GM Performance Parts SB-Chevy SB2.2 NASCAR Race Cylinder Heads

The SB2 NASCAR racing head was first designed to improve durability, simplify preparation procedures, and reduce the overall cost of building and maintaining a small-block racing engine. It has "mirror" design intake ports, and all eight ports are angled toward the center of the engine, making this a perfect choice for single four-barrel applications. Spark plug holes were moved toward the bore center for greater combustion efficiency. This head is designed for aftermarket shaft-mounted rocker arems, and valve spring pads are large enough to use 1.625" springs. The combustion chambers are 48cc, which allow a 12.1:1 compression ratio with flat-top pistons. The head is machined for standard 1/1" valve guides.