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LS7 305cc 4.125" (+) Bore - Single Black Label CNC Cylinder Head - Bare
LS7 305cc 4.125" (+) Bore - Single Black Label CNC Cylinder Head - Bare
LS7 305cc 4.125" (+) Bore - Single Black Label CNC Cylinder Head - Bare
LS7 305cc 4.125" (+) Bore - Single Black Label CNC Cylinder Head - Bare
LS7 305cc 4.125" (+) Bore - Single Black Label CNC Cylinder Head - Bare
LS7 305cc 4.125" (+) Bore - Single Black Label CNC Cylinder Head - Bare
LS7 305cc 4.125" (+) Bore - Single Black Label CNC Cylinder Head - Bare
LS7 305cc 4.125" (+) Bore - Single Black Label CNC Cylinder Head - Bare
LS7 305cc 4.125" (+) Bore - Single Black Label CNC Cylinder Head - Bare
$ 1,525.00

LS7 305cc 4.125" (+) Bore - Single Black Label CNC Cylinder Head - Bare

+

Only left in stock

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.

Download the cylinder head spec sheet

Dimensional Specs

  • Bore Size: 4.125" (+)
  • Weight: 27.5 lbs.
  • Intake Valve Size: 2.250"
  • Exhaust Valve Size: 1.600"
  • Valve Stem Diameter: 5/16"
  • Valve Length: 5.450"
  • Valve Angle: 12°
  • 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 Average Flow: 265
  • Exhaust Average Flow: 177
  • Intake Seat Material: Ductile Iron
  • Intake Port Volume: 305cc
  • Exhaust Port Volume: 106cc
  • Standard Chamber Volume: 70cc
  • 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: OE LS7 1.8 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: OE LS7 1.8 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