Competition Package 65cc Combustion Chamber. Suit S/B Chev

AFR1121

R1121

High flowing AFR 227cc intake port small block Chevy angle plug aluminum cylinder heads are available in two stages of performance. The Race Ready version features 100% CNC ported intakes while the higher flowing Competition version features 100% CNC ported intakes with greater detail. Both come with 100% CNC ported 65cc or 75cc combustion chambers and 80cc exhaust ports with a 3/4" thick head deck (ideal for nitrous or blower applications). In addition we also offer the "as cast" Stage 1 heads for 227cc performance on a budget. Standard valves are lightweight 8mm 2.100 intake and 1.600 exhaust with AFR's hardened ductile iron interlocking valve seats. The 227 has 60/40 valve spacing and piston valve pockets should be checked. The exceptional flow characteristics and 23° valve angle make this the perfect head for 350 to 434 cid engines in drag cars, sprint cars, and late model oval trackers operating from 4500 rpm and up. AFR offset stud girdles are the only special parts required. Some applications require shaft mount rockers or .050 offset rocker arms for durability and reliability of valve train components. Standard rockers can be used but the intake rocker arm will be at a slight angle and the roller tip will not be perfectly centered on the valve tip. Not recommended for street use, unless shaft mount rocker is used. The Exhaust port is raised .250 over GM L-98 cylinder head. Basic Package Components: 100% CNC Ported Combustion Chambers 100% CNC Ported Exhaust Ports 100% CNC Ported Intake Ports 3-angle Radiused Valve Job Bead Lock Intake Valve, 2.080" x .100" long Bead LockExhaust Valve, 1.600" x .100" long 1.550" OD Roller Dual Valve Spring, 225 lbs on seat, .710" maximum lift 10° 4140 Chrome Moly Retainers 10° Bead Lock Valve Keepers 7/16" Rocker Studs Guide Plates Viton Valve Seals Hardened Spring Seat Intake Valve Seats Exhaust Valve Seats Bronze Valve Guides