AFR 65cc Chamber LS Cathedral Port 5.7 Small Bore 230cc CNC Cylinder Heads
Highlights
- 230cc CNC Ported Intake
- Small Bore LS Design
- High RPM Valvetrain
- Assembled Head Pair
Pair of AFR LS Cathedral Port 230cc Fully CNC Ported Cylinder Heads with 65cc Chambers for 1960-1987 Chevy C10s and 1988-1998 Chevy C/K Trucks with 5.7 Small Bore LS Engines.
Support aggressive street and street/strip LS builds with these cylinder heads (1660). Designed for 5.7 small bore applications, they deliver strong airflow and efficient combustion for engines operating at or below 7200 RPM. All intake ports, exhaust ports, and combustion chambers are fully CNC machined for consistent airflow and repeatable performance. A 15-degree valve angle, 65cc combustion chambers, and a competition 5-angle valve job help optimize cylinder filling while maintaining stock port locations.
Features and Benefits:
- Fully CNC ported intake, exhaust, and chambers
- 230cc intake ports support high airflow
- 65cc combustion chambers help optimize compression
- 15-degree valve angle improves airflow efficiency
- Competition 5-angle valve job enhances sealing
- PAC dual valve springs support high RPM operation
- Stainless steel intake and exhaust valves
- Stock cathedral port location for compatibility
- Designed for 5.7 small bore LS engines
Kit Includes:
- 100% CNC ported combustion chambers
- 100% CNC ported intake and exhaust ports
- Competition 5-angle valve job
- 8mm bead lock intake valve, 2.080" x 4.900" overall valve length
- 8mm bead lock exhaust valve, 1.600" x 4.900" overall valve length
- PAC racing spring 1.270" OD hydraulic roller dual valve spring, 155 lbs on seat, .650" maximum lift, 7000-7200 max RPM
- 7-degree chrome moly retainers 1.245" OD x .885" ID x .655" ID
- 7-degree bead lock valve keepers
- Viton valve seals .600" OD x .495" ID
- Hardened valve spring OD locator 1.380" OD x .570" ID
- Ductile iron intake valve seats 2.131" OD x 1.680" ID x .375" deep
- Ductile iron exhaust valve seats 1.650" OD x 1.350" ID x .375" deep
- 8 mm bronze valve guides .502" OD x 2.100" OAL
Specifications:
- Material: A356 aluminum
- Intake port dimensions: 3.250" H x 1.115" W (5/16 top, 3/8 bottom)
- Intake and exhaust port location: Stock
- Exhaust port volume: 86cc
- Exhaust port dimensions: 1.385" H x 1.695" W
- Valve cover bolt pattern: Center bolt
- Valve angle: 15 degrees
- Valve spring pocket diameter: 1.510" OD
- Max valve spring pocket machining: 1.525" OD
- Deck thickness: .750"
- Minimum bore diameter: 3.900"
- Spark plug dimensions: 14mm x .750" with tapered seat
Recommended Components:
- Head gasket: Cometic 3.930" x .040" or AFR #6846
- Intake port gasket: GM or FAST
- Exhaust port gasket: GM #12558573
- Head bolts: (97-03) AFR #6330 or (04+) AFR #6334
- Head studs: (97-03) AFR #6331 or (04+) AFR #6335
- Head bolt washers: Manley AFR #6320
- Suggested intake manifold: FAST 90mm, 92mm, or 102mm
- Spark plug starting range: NGK TR55
Vehicle Fitment:
- 1960-1987 Chevy C10s
- 1988-1998 Chevy C/K Trucks
California Residents: Proposition 65 Warning
Related Categories: C10 Cylinder Heads, C10 Restomod Engine
Only for use on pre-pollution controlled vehicles: This product can be used on vehicles that were manufactured before emissions control regulations were imposed. Pre-pollution vehicles are defined as:
- 1965 and older U.S. manufactured California certified vehicles
- 1967 and older U.S. manufactured federally certified vehicles
