Proflow Cylinder Heads, AirMax 320 CNC, Aluminium, BB Chevrolet, Assembled

Proflow does not sacrifice quality for a low price--you get both with our aluminium cylinder heads. The lightweight heads are cast from A-356 aluminium alloy with a large choice of engine, for SB & BB Chevrolet, LS Chev Holden Ford SB 289-351W, 302, 351 Cleveland 2V & 3V & BB FE, and Chrysler SB & BB. They have phosphorous bronze valve guides, and ductile iron valve seats for use with unleaded gas. They're also end-milled and drilled for accessories. The fully assembled heads have stainless steel valves, high performance valve springs, 7 degree valve locks, rocker arm studs, and guideplates.

This BBC cylinder head is recommended for aggressive street or street/strip applications with displacements up to 540 cubic inches, operating at or below 6800 RPM. 1.625 O.D. Solid Roller, 275lbs on seat, .850 Maximum Lift.

• Material: A356 Aluminum
• Intake Port Volume: 317cc
• Intake Port Dimension: 2.450"H x 1.755"W x 13/32 Radius
• Intake Port Location: Stock
• Exhaust Port Volume: 135cc
• Exhaust Port Dimension: 1.780"H x 2.025" W
• Intake Valve Diameter (in): 2.25 in.
• Exhaust Valve Diameter (in): 1.880 in.
• Combustion Chamber Size: 121cc
• Valve Springs Pocket I.D.: 1.735"
• Maximum Valve Lift (in): 0.750 in.
• Outside Diameter of Outer Spring (in): 1.625 in.
• Lock Style: 10 degree
• Rocker Arm Nut Thread Size: 7/16-20 in.
• Valve Cover Mounting Style: Perimeter bolt
• Intake Valve Angle: 24/4
• Exhaust Valve Angle: 15/4
• Valve Guide Material: Manganese Bronze
• Intake Valve Seat Machine Style: 5-angle
• Valve Seat Material: Mental powder
• Oiling Style: Through pushrod

Recommended Components:

• Intake Port Gasket (.120" Thick)
• Intake Port Gasket (.060" Thick)
• Important: Do not port match your intake manifold to Fel-Pro gasket as it does not precisely fit the heads.
• Exhaust Port Gasket: Head Gasket, Fel-Pro #1047 (Mark V and VI), Head Gasket, Fel-Pro #1017-1 (Mark IV)
• Head Bolts, 7/16"-14 x 7/16"-14 ARP 235-7202: ARP 135-3703 (Mark IV), ARP 135-3707 (Mark V), ARP 235-4713
• Head Bolt Washers: Manley
• Stud Girdle: 7/16 Stud Mount Rocker Arms - 1.7 Ratio (For Optimized Geometry)
• 1.7 Shaft Mount Rocker Arms T&D
• Suggested Manifold: Victor Jr, Super Victor
• Spark Plug Starting Range: Pump Gas 3924 / Race Gas 3922
• 11/32" Intake Valve, 2.250" x5.500" O.A.L
• 11/32" Tulip Exhaust Valve, 1.880" x 5.450" O.A.L
• Racing Spring #1224 1.625 O.D. Solid Roller, 275lbs on seat, .850 Maximum Lift, Max RPM 7400-7600
• 10° Retainers 1.490" O.D x 1.180" I.D x .765" I.D
• 10° 11/32" Valve Locks with lashcap recess
• ARP 7/16" Rocker Exhaust Studs
• ARP 7/16" Rocker Intake Studs
• 3/8" Guide Plates
• 11/32" Viton Valve Seals
• Hardened Spring Cup 1.740" O.D / 1.650" I.D
• 11/32" Intake Manganese Bronze Valve Guides .502" O.D x 2.10" O.A.L
• 11/32" Exhaust Manganese Bronze Valve Guides .502" O.D x 2.25" O.A.L