The Edelbrock part # 77219 Victor 15° Small Block Ford 240cc cylinder head is designed for maximum effort competition racing on 289 - 351+ cubic inch based engines. The inline valve configuration features a 15° valve angle and a modern combustion chamber design allows for high compression without large piston domes. The intake ports are raised .380"; however the intake flange has been extended to maintain proper port alignment with standard intake manifolds. The exhaust ports are patterned with a 2.50" spacing and raised .520" for high flow potential. This head requires shaft mounted rockers; please contact Jesel or T&D for details. Features include 47cc combustion chambers, ductile iron interlocking valve seats, manganese-bronze valve guides and requires professional preparation. Edelbrock recommends 2.125" intake valves and 1.625" exhaust valves with 5.45" overall length. INSTALLATION NOTE: This head requires the use of a 14mm x 3/4" reach, flat gasket spark plug with a heat range appropriate to your application. Deck thickness: 5/8".