Single Plane Intake Manifold- Chevy Small Block V8 Intake Manifold 1957-1986 262ci-400ci, 1987-later with Aluminum Heads HolleyThe 300 261 intake manifolds are designed for square bore carburetor applications on 1957 86 262 400cid Small Block Chevrolet engines and Sbc engines equipped with 1987 91 L98 aluminum Corvette cylinder heads (non Egr applications). Also, these manifolds will work with any Sbc engine equipped with aftermarket cylinder heads, as long as they have a standard port flange opening and mounting bolt locations. The new single plane intake manifold is