Engineered specifically for Gen I Small-Block Chevrolet engines equipped with hydraulic roller camshafts the Performer RPM 210 cc Cylinder Heads are designed as the ideal next-step upgrade from Edelbrock’s Performer series. These premium cylinder heads deliver increased airflow superior quality and exceptional performance for street and strip applications. Manufactured in Edelbrock’s ISO-certified facility in San Jacinto California each head is machined to exacting tolerances for optimal performance and durability. With larger 210 cc intake ports than comparable Performer RPM heads this new design is intended for high-performance builds that require greater airflow and horsepower while maintaining full compatibility with off-the-shelf components. These heads are ideal for 327 c.i. or larger Small-Block Chevrolet engines built between 1955 and 1986 that are not required to meet emission standards. Each Performer RPM 210 cc cylinder head comes fully assembled with premium valvetrain components including stainless steel one-piece swirl-polished intake and exhaust valves with undercut stems for improved flow 2-ring positive oil control seals 3/8" rocker arm studs with 5/16" guide plates hardened steel valve spring locators and Edelbrock Sure-Seat valve springs retainers and keepers. Edelbrock’s patented Clean-Cast™ Technology sets these heads apart by eliminating internal casting flaws and producing smoother internal surfaces thereby significantly improving airflow and coolant circulation. The result is more power and better cooling efficiency right out of the box. Engineered for serious performance applications the Performer RPM 210 cc Cylinder Heads offer exceptional value and power gains for builders and enthusiasts working with Small Block Chevrolet platforms.