Afr 210cc Lsx Cylinder Heads, 66cc Chambers, With Parts

AFR's 210cc LSX heads are the preferred choice over re-worked factory heads. They feature 100% CNC ported intake, exhaust & chambers, A356 aluminum castings, Titanium retainers and high quality components throughout. Recommended for street, towing, or street/strip engines with displacements up to 383 cubic inches, operating up to 6300 RPM. Requires minimum 3.900 bore size for intake valve clearance. Legal for 2005 and older emissions controlled vehicles under CARB EO #D-250-4. Component upgrade and machining options are available to customize AFR Heads to your specific build.
The Small Port, High Velocity Torque Monster!
Designed specifically for 3.900 Bore LSX engines.
For the ultimate high performance street LS1/LS2/LS6 aluminum cylinder head AFR’s all new 210cc emission legal heads (E/O # D250-4) are your only choice. Specifically designed for 1997 to present Gen-3 Chevy Corvettes, Camaros, and trucks using a 3.900 Bore. AFR’s LSX cylinder head offers unmatched flow performance (302 CFM at .600lift) and features 2.020" intake and 1.600" exhaust valves with AFR’s iron ductile interlocking valve seats. With only 210cc port volume (nearly identical to a stock LS1 head) this is an incredible 70 CFM increase over stock casting, creating unbelievable port velocity and performance. The 210cc cylinder head is ideal for naturally aspirated 346 CI to 396 CI engines. It comes standard with 66cc combustion chambers. AFR’s LSX is a direct bolt on, no special parts required. Structural features like Air Flow Research’s trademark 3/4” thick head deck, a must for blown and nitrous applications, reinforced rocker stud bosses, and thick wall runners provide unparalleled durability. An exclusive new modern combustion chamber design with double quench pad area helps the LSX generate huge low and mid lift airflow numbers. If you need a snake charmer for that pesky neighborhood “Cobra Mustang” look no further!

Note: Hydraulic roller cams in "LS" Gen III engines typically experience valve float at 6600-6800 RPM's. If you are using aftermarket rocker arms valve float will become prominent and AFR highly recommends upgrading to the AFR part #8019 spring. If you plan on running over .600 gross valve lift and/or 6600 RPM, AFR suggests you upgrade your springs to AFR part #8019. The upgraded springs have higher seat and open pressures (155/410+) to better reduce the risk of valve float in more aggressive applications.
Note: LSX bead locks and aftermarket bead locks are not interchangeable. GM made their bead lock radius and depth different. AFR locks are the same as GM LSX.

Basic Package Components Part # 100% CNC Ported Combustion Chambers
100% CNC Ported Exhaust Ports
100% CNC Ported Intake Ports
Competition 3-angle Radiused Valve Job
8mm Bead Lock Intake Valve, 2.020” x 4.900" Overall Valve Length AFR #7207 8mm Bead Lock Exhaust Valve, 1.600” x 4.900" Overall Valve Length AFR #7228 PAC Racing Spring 1.290" OD Hydraulic Roller Dual Valve Spring,
140 lbs on seat, .600" maximum lift, Max RPM 6300-6500 AFR #8017 *LSX bead locks and aftermarket bead locks are not interchangeable. GM made their bead lock radius and depth different. AFR locks are the same as GM LSX. *Notes
7° Titanium Retainers 1.245" O.D x .885" I.D x .655" I.D AFR #8512 7° Bead Lock Valve Keepers AFR #9007* Viton Valve Seals .600" O.D x .495" I.D AFR #6612 Hardened Valve Spring O.D Locator 1.380" O.D x .570" I.D AFR #8042 Ductile Iron Intake Valve Seats 2.131" O.D x 1.680" I.D x .375" Deep AFR #9059 Ductile Iron Exhaust Valve Seats 1.650" O.D x 1.350" I.D x .375" Deep AFR #9069 8 mm Bronze Valve Guides .502" O.D x 2.100" O.A.L AFR #9051
Specifications, Features, and Optional Supporting Components Head Torque 11mm ARP 70ft. lbs. w/ Moly Head Torque 8mm 23ft. lbs. w/ Moly Exhaust Port Gasket GM#12558573 Intake Port Gasket
GM or FAST Head Gasket, Cometic 3.930 .040" AFR #6846 Head Bolts (97-03) AFR #6330 Head Studs (97-03) AFR #6331 Head Bolts (04+) AFR #6334
Suggested Manifold FAST 90mm, 92mm, or 102mm  Intake Port Volume 210cc Exhaust Port Volume 84cc
Combustion Chambers 66cc Spring Pocket  1.510" O.D to1.525, no deeper  Valve Spacing Stock
Head Bolt Washers, Manley AFR #6320 Valve Angle 15° Flat Mill (Milling options available) .006" per cc 58cc Maximum Important: Do not port match you intake manifold to any Fel-Pro gasket as it does not precisely match AFR heads.
Note: Milling head deck will affect flow numbers.