AFR 24° BBC Cylinder Head 325cc Partially CNC Ported, Race Ready, w/121cc CNC Chambers

AFR 24° BBC Cylinder Head 325cc Partially CNC Ported, Race Ready, w/121cc CNC Chambers

The AFR 325cc BBC Rectangle Port Cylinder Head is designed for aggressive street and street/strip big block Chevy applications with displacements up to 540 cubic inches, operating at or below 6800 RPM. Featuring partially CNC-machined intake and exhaust ports, along with fully or partially CNC-machined combustion chambers, this head delivers outstanding airflow performance, reaching 390 CFM at 0.700″ lift.

Included Components

• 50% CNC Ported Combustion Chambers
• 20% CNC Ported Exhaust Ports
• 30% CNC Ported Intake Ports
• Competition 5-Angle Valve Job
• 11/32″ Intake Valve, 2.300″ x 5.500″ O.A.L – AFR #7626
• 11/32″ Nail Head Exhaust Valve, 1.880″ x 5.450″ O.A.L – AFR #7631
• PAC Racing #1224 1.625” OD Solid Roller Dual Valve Spring, 275 lbs. on seat, .850” maximum lift, Max RPM 7400-7600 – AFR #8031
• 10° Steel Retainers 1.500″ O.D x 1.168″ I.D x .844″ I.D – AFR #8518
• 10° 11/32″ Valve Keepers with lash cap recess – AFR #9005
• ARP 7/16″ Rocker Studs (Intake) – AFR #6407
• ARP 7/16″ Rocker Studs (Exhaust) – AFR #6406
• Adjustable 3/8″ Guide Plates – AFR #6109
• 11/32″ Viton Valve Seals – AFR #6613
• Hardened Spring Cup 1.740″ O.D / 1.650″ I.D – AFR #8046
• Intake Valve Seats 2.450″ O.D x 2.000″ I.D x .375″ Deep – AFR #9065
• Exhaust Valve Seats 2.000″ O.D x 1.580″ I.D x .375″ Deep – AFR #9064
• 11/32″ Intake Bronze Valve Guides .502″ O.D x 2.10″ O.A.L – AFR #9041
• 11/32″ Exhaust Bronze Valve Guides .502″ O.D x 2.25″ O.A.L – AFR #9042

Performance Flow Chart (325cc w/ 100% CNC Chamber)

Specifications & Features

• Material: A356 Aluminum
• Intake Port Volume: 325cc
• Exhaust Port Volume: 132cc
• Combustion Chamber Size: 117cc (As Cast) / 121cc (Full CNC)
• Valve Angle: 24°/4° Intake, 15°/4° Exhaust
• Deck Thickness: .750″
• Minimum Bore Diameter: 4.250″
• Spark Plug Dimensions: 14mm x .750″ w/ Gasket Seat

Important Notice

CARB Status: These products are illegal to operate on any public highway, road, or park. They are only legal for use on dedicated racing vehicles. Violations are subject to fines up to $37,500 per violation per vehicle, possible revocation of registration, and loss of public road usage rights.