DART PRO 1 227cc CNC Ported Aluminum Cylinder Heads
- 227cc runner
- 66 cc Chamber
- Angle Plug
- 1.550" double springs available
- FULLY CNC PORTED Competition Cylinder Heads
This head is recommended for Maximum Performance & Full Competition, Heads-Up & Super Classes, over 7000 rpm, 400+ ci
Dart PRO 1 CNC heads are professional quality competition cylinder heads. Every intake port, exhaust runner, valve bowl, and combustion chamber is 100% CNC machined on special dedicated DART PRO 1 castings. CNC machined 227cc intake ports give you optimized flow characteristics out of the box. DART 5-axis machining centers precisely duplicate the port profiles so that every head delivers awesome performance. CNC machined combustion chambers ensure that every chamber has the same volume so that every cylinder has equal compression.The valve seats are machined, not ground, to produce precise angles and radiuses for maximum airflow.
DART PRO 1 aluminum cylinder heads for small-block V8’s deliver advanced airflow technology at an unbeatable price! There’s a DART PRO 1 head for virtually every small-block engine. DART offers a choice of four intake runner sizes (180cc, 200cc, 215cc, and 230cc), two chamber volumes (64cc and 72cc), five valve diameters, and straight or angled spark plugs. DART has improved the original small-block design with extra-thick decks and high-capacity water jackets that increase reliability in high-performance applications. Hardened exhaust seats and long-lasting mag-bronze valve guides significantly extend cylinder head life. DART PRO 1 heads are engineered for easy installation. They use standard small-block pistons, headers, and valvetrain components, and are bolt-on replacements for most conventional 23° heads.
Dart 227 CNC Port SBC 23 Aluminum Cylinder Heads
Part# 11970040 - 11971143
Material: 355T6 Aluminum
Combustion Chambers: 66cc for 4.155" Bore
Intake Valve Dia: 2.08
Intake Port volume: 2.200" x 1.310"
Int Port Location: Stock
Intake Gasket: Fel-Pro# 1206
Exh Valve Dia.: 1.60"
Exh Port volume: 85cc
Exhaust Port Dim: 1.410" x 1.585"
Exh Port Location: Stock location and bolt pattern
Exhaust Gasket: Fel-Pro# 1405
Flow, Intake: 309@ .700" lift / 28"
Flow, Exhaust: 226cfm @ .700" lift / 28"
Head Bolts: Stock bolts can be used. We recommend ARP# 134-3601
Head Studs: ARP# 134-4001 or 234-4301 (12pt)
Manifold: Alum Single Plane Dart (opening - 1.100"x 2.000") 5.500" tall
Milling: Min. 63cc = .020” (.0065” = 1cc) Flat Mill, Angle mill .100” safely / .150” = 55cc (carefully)
Pistons: Most 23°aftermarket pistons.
Push Rod length: Stock thru +.100" Should always measure (Stock length = 7.800")
Push rod Guide Plate: Must use Comp Cam # 4808 (flat)
Retainers: Titanium (10°)
Spark Plug: Angle or straight, .750" reach, gasketed, Autolite AR3933
Spring Pockets: 1.550" OD (.030" deeper max)
Springs: 1.550D = 195# @ 1.900" / .690" max Comp 954
Valve Length: 5.015" (+.100) w/ 1.550
Valve Stem Dia: .3415" - 11/32"
Valve Train: Std SBC 3/8" or 7/16" Rocker Studs
Valve Guides: 1/2" OD Int = Mag-bronze Exh = Phos-bronze (.002" press)
Valve Guide length: 1.950"
Valve Guide clearance: .0014" - .002" (with our .3415 dia. valve stem)
Valve Guide Spacing: 1.890" moved .030" from stock
Valve Seats: Hardened Ductile Iron, .006 Press
Valve Seat dim. Int - 2.160"x 1.810" x .350", Exh - 1.650"x 1.350"x .350"
Valve Seat angles: Int = 32° - 45° - 60° - 70° Exh = 37° - 45° - radius
Stud Girdle: Use any standard SBC stud girdle
Torque Specifications:
Rocker Studs = 45 ft/lb
Manifold = 35 ft/lb
Head Bolts = 70 ft/lbBlock Use: Any SBC Iron or Aluminum
Weight: 23 lbs bare, 28 lbs assembled
This product was added to our catalog on Wednesday 19 July, 2006.
