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- Big Block-Chevy Iron Eagle Cylinder Head
- 308cc Intake Ports
- 119cc Combustion Chambers
- 2.25'' Int/1.88'' Exh Valves
- 1.550'' Springs, 145lbs @ 1.900''
- .660'' Max Lift
- Assembled, Sold Individually
SpecificationMaterial: Superior cast iron alloy
Combustion Chambers: 119cc
Intake Valve Dia: 2.25'
Intake Port Dim: Int Port Location: Stock
Intake Gasket: Mr. Gasket 720-121
Exhaust Valve Dia: 1.88'
Exh Port Volume: 129cc
Exh Port Dim: 1.670' x 1.800'
Exh Port Location: Raised .300' Standard Bolt Pattern
Exhaust Gasket: Fel-Pro 375-1412
Exhaust Bolts: 1' longer than stock (4) ea.
Flow, Intake: 363cfm @ .800' lift
Flow, Exhaust: 266cfm @ .800' Lift
Manifold: Rectangular Port Dart (opening - 1.575' x 2.250') 6.25' tall
Milling: Min 110cc (.005' = 1cc) Flat Mill only
Pistons: Most aftermarket pistons
Push Rod Length: Avg +.200' / +.250' Should always measure; Stock Length Int = 8.275' / Exh = 9.250'
Retainers: 1.625' - Titanium / 1.550' - Moly Steel 10°
Spark Plug: .750' reach, gasketed, Champion C59C / C59YC Street RC12YC
Spring Cups: 1.625' - .035 cup / 1.550' - ID locator
Springs: 1.550' Single Springs, 145lbs @ 1.900', .660' Max Lift Comp Cams 249-936
Stud Girdle: Must use Dart design 301-64110001
Valve Angles: Int - 24°, Exh - 15° (Rolled 2°) 4° cant
Valve Length: Int - 5.475' (+.250') Exh - 5.435' (Stock)
Valve Stem Dia: 11/32'
Valve Train: Standard BBC 7/16' stud mount
Valve Guides: 1/2' OD Mag-bronze Cut for .530' PC seals (.002' press)
Valve Guide Length: Int - 2.100' Exh - 2.250'
Valve Guide Clearance: .0014' - .0021' (with 11/32' dia valve stem)
Valve Guide Spacing: Exh moved .045' away from Int
Valve Seats: Exh = Tungsten hardened alloy, .006' press (TIR .004)
Valve Seat Dim: Exh - 2.000' x 1.600' x .375'
Valve Seat Angles: Int = 32° - 45° - 60° - 70°, Exh = 37° - 45° - radius
Valve Covers: 301-68000040
Torque: Head Bolts = 70 ft/lbs; Rocker Studs = 45 ft/lbs; Manifold = 35 ft/lbs
Block Use: Mark IV, Gen V, Gen VI with proper head gasket
Weight: 70 lbs

![Valve Spring Compressor [Stud Mount]](https://www.jegs.com/images/mini_200/500/555/555-80518.jpg)

![Valve Spring Compressor [Stud Mount]](https://www.jegs.com/images/mini_200/500/555/555-80521.jpg)

