Fits 429 and 460 ci engines (except BOSS 429) Valve angles and locations designed to reduce cylinder wall shrouding and improve flow Combustion chambers designed to accommodate centrally located valves Production 429 Cobra Jet intake and exhaust manifolds bolt on Production Ford 429/460 valve cover bolt pattern M-6582-C460 Ford Racing Valve Covers recommended 2.200" intake valve, 1.76" exhaust valve Flows approximately 330 CFM intake and 225 CFM exhaust 72cc combustion chambers 290cc intake runner, 148cc exhaust runner Uses rocker arm part numbers M-6564-A460 Assembled with solid roller springs: Closed seat pressure 240# @ 1.900"; Open seat pressure 625# @ 1.200"; Max lift .650" Machined 10-degree locks and steel valve spring retainers, premium valve seals Uses Motorcraft AGSP series spark plugs NOTE: If replacing Ford Racing or production 429 Cobra Jet heads, new intake valve notches are required NOTE: Uses Felpro exhaust gasket part number 1420, Uses Felpro® intake gasket part number 1231