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AFR - Airflow Research 3834

AFR - Airflow Research 300cc Bullitt Series Cylinder Heads 300cc Intake Ports


Free Shipping Ships directly from the manufacturer on 10/29/19
Save $10 off $199, $45 off $499, $100 off $999. Promo Code: FALLFUN exclusions apply

AFR - Airflow Research 300cc Bullitt Series Cylinder Heads 300cc Intake Ports $2,888.00
Out of stock
300cc Bullitt Series Cylinder Heads
  • 300cc Intake Ports
  • 75cc Combustion Chambers
  • 2.300'' Int / 1.760'' Exh Valves
  • 1.550'' Dia. Springs
  • Hydraulic Roller 175# Seat Pressure
  • 10° Steel Retainers
  • .250 Raised Exh Port
  • Assembled 2/pkg
  • AFR - Airflow Research 3834 Details

    300cc Bullitt Series Cylinder Heads

  • 75cc Combustion Chamber Volume
  • .250'' Raised Exhaust Port Location
  • Cylinder Head Specifications
  • Material: A356 Aluminum
  • Intake Port Volume: 300cc; 2.275'' H x 1.850'' W x .575 Radius; Stock Location
  • Exhaust Port Volume: 142cc; 1.850'' H x 1.600'' W; .250'' Raised Port Location
  • Combustion Chamber Volume: 75cc
  • Valves: 2.300'' dia. x 5.245'' o.a.l. Intake / 1.760'' dia. x 5.050'' o.a.l. Exhaust ( 11/32'' Stem Diameter )
  • Valve Springs: (PAC Racing) Hydraulic Roller 1.550'' Diameter - Closed Pressure: 175 lbs.; Max Lift: .725''
  • Spring Retainers: 1.500'' O.D. x 1.120'' I.D. x 0.705''I.D. - 10° Manley Steel Retainers
  • Valve Locks: 10° 11/32'' Beadlock with Lash Cap Recess
  • Rocker Studs: 7/16'' (ARP)
  • Guide Plates: 3/8'' Adjustable
  • Valve Seals: 11/32'' Viton
  • Hardened Valve Spring I.D. Locator: 1.550'' O.D. x 0.780'' I.D.
  • Intake Valve Seats: 2.450'' O.D. x 1.950'' I.D. x 0.375'' Deep
  • Exhaust Valve Seats: 1.900'' O.D. x 1.400'' I.D. x 0.375'' Deep
  • Valve Guides: 11/32'' Bronze, 0.531'' O.D. x 2.250'' O.A.L.
  • Valve Spring Pocket Diameter: 1.750'' O.D.
  • Deck Thickness: 0.750''
  • Minimum Bore Diameter: 4.360''

    Facts and Related Components
  • Intake Gasket: SCE p/n 829-235104
  • Head Gasket: (4.500'' Bore Gasket) Fel-Pro p/n 375-1018, Cometic p/n 245-C5667-040
  • Exhaust Gasket: Fel-Pro p/n 375-1420
  • Head Bolts: ARP p/n 070-155-3603
  • Head Studs: ARP p/n 070-155-4203 (12-point)
  • Head Bolt Washers: AFR p/n 033-6320
  • Spark Plug Specs: 14mm Thread, .750'' (3/4'') Reach, Gasket Seat
  • Valve Angle: 14° Intake / 8° Exhaust
  • Pushrod Slots: Standard
  • Pushrods: Check pushrod clearance with head installed on the engine block before final assembly
  • Stud Girdle: AFR p/n 033-6209
  • Rocker Arms: Standard
  • Lifters: Standard
  • Spring Pockets: May not be cut any larger than 1.750''
  • Accessory Bolt Holes are Drilled
  • Recommended Intake Manifold: AFR Single Plane 4150 Carb Pad (p/n 033-4992) / 4500 Carb Pad (p/n 033-4993)

  • The Ultimate 14° BBF Race Heads

    ''Blue Oval'' big block performance is alive and well at Air Flow Research with a much needed clean sheet redesign of the aging BBF cylinder head. Starting with the needlessly large OEM port their design team decreased overall runner size while giving it a more consistent cross sectional area. This change is designed to increase peak power while notably boosting the torque, responsiveness and fuel efficiency. They carefully shaped the combustion chamber and positioned the valves to compliment intake and exhaust port design while efficiently utilizing the cylinder bore. The improvement in valve positioning allowed them to address the ''Achilles Heel'' of the BBF head, the exhaust port. By filling the floor of the exhaust port without raising the height AFR has improved high flow lift while increasing flow at low and mid lifts, achieving a 75% intake to exhaust flow ratio with their exhaust port in the stock location reaching 284 cfm with these 142cc ports. These high flow heads feature a .250'' raised exhaust port location. Stock header and chassis fitment may be an issue for tight engine compartments and chassis.

    The 300cc heads are AFR's largest and best flowing BBF heads! They feature 100% CNC ported intake, exhaust & chambers, A356 aluminum castings, and high quality components throughout. These heads are best suited for large displacement high RPM Big Block Ford racing engines or radical ''Pro Street'' style builds. Application specific pistons or fly cutting of your current pistons are required due to the revised valve locations and angles of the AFR Bullitt heads. .

    300cc Bullitt Street Cylinder Head Features:
  • 100% CNC Ported Combustion Chambers
  • 100% CNC Bowl Blend Exhaust Ports
  • 100% CNC Bowl Blend Intake Ports
  • Competition 5-angle Valve Job
  • 300cc Intake Ports
  • 142cc Exhaust Ports
  • Intake Valve, 2.300'' x 5.245'' Overall Valve Length
  • Exhaust Valve, 1.760'' x 5.050'' Overall Valve Length
  • Hydraulic Roller Valve Spring: 1.550'' OD Dual Spring, 175 lbs. on seat, .725'' max lift (Max RPM 6500-6700)
  • Solid Roller Valve Spring: 1.625'' OD Dual Drag Race Spring, 275 lbs. on seat, .850'' max lift (Max RPM 7400-7600)

  • Some parts are not legal for use in California or other states with similar laws / regulations

    Motor Vehicles

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    Electrical Cords

    WARNING: The wires of these products contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. Wash hands after handling.