Mast Motorsports Factory Mast 4.065" Bore LT Heads - 2.165" Valve Size

The Mast Motorsports cylinder head product line is completely manufactured from a raw casting to a finished cylinder head in the USA located in Nacogdoches Texas.
Mast refuses to compromise on materials and methods that may jeopardize longevity, performance, and quality.  When buying Mast Cylinder heads, you are getting the highest level of quality and performance on the market.
Full Send, no compromises, no shortcuts, ever.
Dimensional Specs
Bore Size: 4.065" (+)
Weight: 30 lbs.
Intake Valve Size: 2.126" OE/2.165" Large Valve
Exhaust Valve Size: 1.590"
Valve Stem Diameter: 8mm
Valve Length: 5.550"
Intake Valve Angle: 12.5°x2.61°
Exhaust Valve Angle: 12°x2.38°
Valve Spring Pocket Diameter: 1.325"
Valve Spring Install Height: 1.880"
Head Stud Size: .472"
Valve Guide OD: .500"
Valve Job Type: Newen CNC 5 Angle
Air Flow & Performance Criteria
Intake Max. Flow: 350 CFM OE / 379 CFM Large Valve @ 0.700"
Exhaust Max. Flow: 214 CFM @0.700"
Intake Average Flow: 251 CFM OE / 270 CFM Large Valve
Exhaust Average Flow: 157 CFM
Intake Seat Material: OE Seat Material/Ductile Iron (Large Valve)
Intake Port Volume: 301cc
Exhaust Port Volume: 112cc
Standard Chamber Volume: 60cc
Port Type: CNC
Materials
Cylinder Head Material: 319-T7 Aluminum
Intake Valve Seat Material: OE Seat Material/Ductile Iron (Large Valve)
Exhaust Valve Seat Material: OE Seat Material
Deck Thickness: .300"
Rocker Stand Type: Pedestal
Rocker Arm Type: LS7 Exhaust 1.8 Ratio
Guide Material: Powdered Metal
General
Rocker Stand Type: Pedestal
Rocker Stands Included: Built-In
Rocker Stand Dowels Included: N/A
Uses Stock Rocker Bolts: No
Rocker Bolts Included: No
Rocker Arm Type: LS7 Exhaust 1.8 Ratio
Head Bolt QTY: 4 Bolt Style
Valve Cover Rail Height: + ½ inch
Can use OE Valve Cover: Yes
Custom Options Available