C-Series Aluminum Intake Manifold Ford Inline-6

The Offenhauser 6227C C-Series intake manifold is engineered to bridge the gap between stock and full competition setups for Ford 240 and 300 cubic inch inline-six engines. Constructed from durable aluminum, this manifold is designed to enhance torque output in the mid to upper RPM range, with a broad power band spanning from 2,500 to over 7,000 RPM. It features a natural aluminum finish and is compatible with square bore carburetors, including Holley and Carter models, with a recommended CFM of 500 and larger. The manifold includes rear openings for 3/8" and 1/4" NPT fittings and allows for emission control provisions to be blocked off for competition use. While often listed as fitting through 1981, the 6227C manifold has been found to physically fit Ford 300 inline-six engines and cylinder heads much later, through at least 1989 and often into the early 1990s, with compatibility primarily referencing accessory mounting and minor head changes. Minor adjustments for water passage plugs or linkage may be necessary on later heads or with automatic transmissions. This manifold is specifically designed for the larger 240-300ci engines and will NOT fit the 200ci 6-cylinder. When pairing with headers, Clifford headers are not recommended due to fitment issues. Hooker and Hedman headers are generally compatible, with Hedman often cited for the best fit. Borla headers do NOT fit with Offenhauser manifolds due to clearance issues. It is important to use the correct header installation kit, especially on 1981 and newer engines, as these kits provide necessary spacers and clamps. An Offy universal linkage accessory kit is also recommended for most installations.