Rectangular-port big block Chevy cylinder head offers increased flow and velocity compared to standard oval-port cylinder head, particu-larly between 3500-7000 RPM. Open 118cc combustion chambers and 315cc/300cc intake runners provide maximum performance potential. Stainless 2.19" intake and 1.88" exhaust valves have 11/32" stems (smaller than original) to reduce valve train weight. Deck surface was specifically designed for compatibility with all big block Chevy engine blocks. Sold individually, bare or completely assembled.
- Cylinder Head Style:
- Assembled
- Cylinder Head Material:
- Cast aluminum
- Cylinder Head Finish:
- Natural
- CNC-Machined Combustion Chamber:
- No
- Combustion Chamber Volume (cc):
- 118cc
- Combustion Chamber Style:
- Semi-open
- CNC-Machined Intake Runner:
- No
- Intake Runner Volume (cc):
- 315cc/300cc
- Intake Port Shape:
- Rectangular
- Intake Port Location:
- Standard
- Intake Valve Angle:
- 26 degree
- CNC-Machined Exhaust Runner:
- No
- Exhaust Runner Volume (cc):
- 110cc
- Exhaust Port Shape:
- Round
- Exhaust Port Location:
- Standard
- Exhaust Valve Angle:
- 17 degree
- Intake Valves Included:
- Yes
- Intake Valve Diameter (in.):
- 2.190 in.
- Exhaust Valves Included:
- Yes
- Exhaust Valve Diameter (in.):
- 1.880 in.
- Valve Type:
- Stainless
- Maximum Valve Lift (in.):
- 0.700 in.
- Valve Springs Included:
- Yes
- Valve Spring Type:
- Dual
- Outside Diameter of Outer Spring (in.):
- 1.540 in.
- Valve Guides Included:
- Yes
- Valve Guide Material:
- Manganese bronze
- Valve Seats Machined:
- Yes
- Valve Seat Material:
- Ductile iron
- Valve Seat Machine Style:
- 3-angle
- Retainers Included:
- Yes
- Retainer Material:
- Steel
- Valve Stem Seals Included:
- Yes
- Valve Stem Seal Style:
- PTFE Positive stop
- Locks Included:
- Yes
- Lock Style:
- 7 degree steel
- Camshaft Style:
- Hydraulic flat tappet
- Spark Plug Style:
- Angled
- Guideplates Included:
- Yes
- Guideplate Pushrod Size:
- 3/8 in.
- Rocker Arm Studs Included:
- Yes
- Rocker Arm Nut Thread Size:
- 7/16-20 in.
- Accessory Bolt Holes Drilled:
- Yes
- Valve Cover Mounting Style:
- Perimeter bolt
- Heat Crossover:
- No
- Steam Holes Drilled:
- No
- Oiling Style:
- Through pushrod
- Machined for O-Ring:
- No
- Quantity:
- Sold individually.
- Notes:
- Spark plug is closer to center of bore and will interfere with high-dome pistons designed for open chamber heads. Use pistons designed for these heads if a large dome is desired.
- Make:
- Chevrolet
- Engine Family:
- Chevy big block Mark IV
- Engine Sizes:
- 6.5L/396-7.4L/454
- Years:
- 1966-1990
- Engine Family:
- Chevy big block Gen V
- Years:
- 1991-1995
- Engine Family:
- Chevy big block Gen VI
- Years:
- 1996-2000
- Engine Sizes:
- 7.4L/454
