Dart Machinery CNC Ported Pro-1 Chev SB Heads
CNC ported heads are no longer just for the pros. Every intake port, every exhaust runner, every valve bowl, and every combustion chamber is 100% CNC machined on special dedicated PRO1 castings. Flows 309 cfm (at .700" lift) intake and 226 cfm exhaust.
Assemblies include 2.080"/1.600" valves, 1.550" roller springs, 10 deg. titanium retainers with machined locks, studs, and guide plates.
Note: chambers are designed for 4.125" bore or larger.
Part Type: Cylinder Head
Application: Chevrolet Small Block
Cylinder Head Material: Aluminum
Bare or Assembled: Assembled
Combustion Chamber Size: 66cc
CNC Machined Combustion Chambers: No
Intake Valve Angle: 23
Exhaust Valve Angle: 23
Intake Port Volume: 227cc
CNC Machined Intake Port: No
Intake Port Flow: 309 cfm @ .700" Lift / 28"
Intake Port Location: Standard
Intake Port Shape: Rectangular
Intake Port Dimensions: 2.200" x 1.310"
Suggested Intake Gaskets: Fel-Pro 1206 or Equivalent
Exhaust Port Volume: 85cc
CNC Machined Exhaust Port: No
Exhaust Port Flow: 226 cfm @ .700" Lift/ 28"
Exhaust Port Location: Standard
Exhaust Port Shape: Square
Exhaust Port Dimensions: 1.410" x 1.585"
Suggested Exhaust Gaskets: Fel-Pro 1404 or Equivalent
Spark Plug Style: Angled
Suggested Spark Plug: .750” reach, 14mm hex
Valve Guides: Yes
Valve Guide Spacing: 1.890" exhaust moved .030" from intake
Valve Stem Diameter: 11/32" (.3415")
Valve Seats: Yes
Valve Job: Multi-Angle
Intake Valve Diameter: 2.080"
Intake Valve Included: Yes
Exhaust Valve Diameter: 1.600"
Exhaust Valve Included: Yes
Suggested Valve Length: 4.965"
Valve Spring Pockets: 1.550" (Can cut .030" deeper MAX.)
Valve Springs Included: Yes, 1.550" Dual
Valve Spring Application: Mechanical Roller, 230lbs. Seat, 550lbs. Open, .750" Max Lift
Valve Springs Retainers Included: Yes
Valve Locks Included: Yes (10 Degree)
Valve Seals Included: Yes
Rocker Studs Included: Yes (7/16")
Guide Plates Included: Yes
Valve Cover Mounting Style: Center Bolt and Perimeter
Steam Holes Drilled: No
Heat Crossover: No
Suggested Head Bolts: ARP 134-3601 or Equivalent
Suggested Head Studs: ARP 134-4001 or Equivalent
Suggested Stud Girdle: Power Products 43101K, Howards Cams 90101, Jomar 1104
Head Bolt Torque with Oil: 70 ft./lbs.
Rocker Stud Torque with Oil: 45 ft./lbs.
Intake Bolt Torque with Oil: 35 ft./lbs.
Manufacturer: Dart Machinery
Manufacturer's Part Number: 11971143P
Weight:
Warranty: Race Application, No warranty expressed or implied
Quantity: Sold as Each |