Cathedral Port 5.3L 3.780" (+) Bore - Pair Black Label CNC Cylinder He

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. 

Cylinder Head Specs Click HERE

Full Send, no compromises, no shortcuts, ever.

Dimensional Specs

• Bore Size: 3.780" (+)
• Weight: 29 lbs.
• Intake Valve Size: 2.040"
• Exhaust Valve Size: 1.570"
• Valve Stem Diameter: 5/16"
• Valve Length: 5.450"
• Valve Angle: 11°
• Valve Spring Pocket Diameter: 1.65"
• Valve Spring Install Height: 1.800"
• Head Stud Size: .493"
• Valve Guide OD: .502"
• Valve Job Type: Newen CNC 5 Angle

Air Flow & Performance Criteria

• Intake Max. Flow: 330 CFM @ 7.000"
  
• Exhaust Max. Flow: 240 CFM @ 7.000"
• Intake Average Flow: 218 CFM
• Exhaust Average Flow: 171 CFM
• Intake Seat Material: Ductile Iron
• Intake Port Volume: 252cc
• Exhaust Port Volume: 99cc
• Standard Chamber Volume: 62cc
• Port Type: CNC
  

Materials

• Cylinder Head Material: A356-T6 Aluminum
• Intake Valve Seat Material: Ductile Iron
• Exhaust Valve Seat Material: Ductile Iron
• Deck Thickness: .750"
• Rocker Stand Type: Mast Billet
• Rocker Arm Type: LS3 1.7 or Aftermarket
• Guide Material: Phosphor Bronze

General

• Rocker Stand Type: Mast Billet
• Rocker Stands Included: Yes
• Rocker Stand Dowels Included: Yes
• Uses Stock Rocker Bolts: No
• Rocker Bolts Included: No
• Rocker Arm Type: LS7 1.7 or Aftermarket
• Head Bolt QTY: 6 Bolt Style
• Valve Cover Rail Height: + ½ inch
• Can use OE Valve Cover: Yes

Custom Options Available

• Chamber Softening
• Custom Chamber Sizing
• ½ inch head stud clearance
• Copper Exhaust & Intake Valve Seats