Our max effort cathedral port head for the LSX platform is recommended for race applications or radical "Pro Street" builds with displacements up to 454 cubic inches, operating at or below 6800 RPM. Requires a minimum bore size of 4.000" to clear the supplied 2.165" intake valve.
245cc Large Bore LSX Aluminum Cylinder Head Flow Chart
Tested on 4.155 bore
Included Components
- 100% CNC Ported Combustion Chambers
- 100% CNC Ported Exhaust Ports
- 100% CNC Ported Intake Ports
- Competition 5-angle Valve Job
- 8mm Bead Lock Intake Valve, 2.165" x 4.900" Overall Valve Length: AFR #7211
- 8mm Bead Lock Exhaust Valve, 1.600" x 4.900" Overall Valve Length: AFR #7228
- PAC Racing Spring 1.270" OD Hydraulic Roller Dual Valve Spring, 155 lbs. on seat, Max RPM 7000-7200: AFR #8019
- 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 2.200" O.D x 1.750" I.D x .375" Deep: AFR #9060
- 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
*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.
Recommended Components:
- Intake Port Gasket: GM or FAST
- Exhaust Port Gasket: GM #12558573
- Head Gasket, Cometic 4.200 .040": AFR #6845
- Spark Plug Starting Range: NGK TR55
Specifications & Features:
- Material: A356 Aluminum
- Intake Port Volume: 245cc
- Intake Port Dimension: 3.315"H x 1.145"W x 11/32 top 13/32 bottom
- Intake Port Location: Stock
- Exhaust Port Volume: 88cc
- Exhaust Port Dimension : 1.495" H x 1.730" W
- Exhaust Port Location: Stock
- Combustion Chamber Size: 65cc or 73cc
- Valve Cover Bolt Pattern: Center Bolt
- Valve Angle: 15°
- Valve Spring Pocket Diameter: 1.510" O.D
- Max Valve Spring Pocket Machining: 1.525" O.D
- Deck Thickness: .750"
- Minimum Bore Diameter: 4.000"
- Flat Mill - 65cc chamber: .006" per cc 58cc Maximum
- Flat Mill - 73cc chamber: .006" per cc 65cc Maximum
- Minimum Cross Sectional Area: 2.680 sq. in.
- Spark Plug Dimensions: 14mm x .750" w/Gasket Seat
