Performer RPM small-bore cylinder heads from Edelbrock are designed for use with 265, 283, 305, and 307 cid small-block Chevy engines with 3.736” to 4.000” bores produced from 1954 to 2003. They have the same great features as every Performer RPM series cylinder head—thick deck, extra-thick port walls, high-flowing ports, ductile iron seats, and high-quality rocker studs—plus state-of-the-art compact combustion chambers and efficient ports that offer improved performance throughout the RPM range. Builders will also find threaded inserts in the rocker studs and exhaust bolt holes for superior strength and durability, as well as manganese-bronze valve guides. Sold singly.
- For 1954–2003 small-block Chevy engines with 3.736” to 4.000” bores.
- For SBC engines with 265, 283, 305, or 307 cubic inch displacement.
- Valve spacing has been reduced to 1.817” to accommodate the smaller bores.
- Retains stock straight spark plug angle and exhaust flange bolt pattern.
- Uses the early Gen 1 (1959–1986) valve cover bolt pattern.
- Cast from A356 aluminum and heat treated to T-6 specs.