Mast Black Label GM LS7 305cc/70cc 12° CNC Cylinder Heads w/Valves – CH-LS7-600247

Mast Motorsports offers the most comprehensive LS & LT Line of Cylinder Heads. Starting with a raw casting, and complete the machining process 100% in house. Mast designs and manufacture their castings exclusively with their foundry partner.Mast Castings have been designed to withstand the extremes of all forms of racing and performance.Manufactured from A356 T6 Material, they are fully heat treated and pressure tested. Mast completes the manufacturing process using state of the art Hurco 5 Axis CNC machines – from raw casting to completed head in Nacogdoches, Texas. A premium casting and cylinder isn’t complete unless you match it with premium components.Mast exclusively utilizes Made in the USA CHE Valve Seats and Valves Guides to complement the premium Black Label Cylinder Heads. There is no question CHE offers the best and finest in materials, machining, and longevity that ensures years of performance and quality. Finishing and valve jobs are completed using only the best CNC valve job process utilizing a Newen CNC valve cutting machine.

Dimensional Specs

• Bore Size:4.125″ (+)
• Weight:27.5lbs.
• 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 Max. Flow:405 CFM @ 0.700″
• Exhaust Max. Flow:254 CFM @ 0.700″
• Intake Average Flow:265 CFM
• Exhaust Average Flow:177 CFM
• 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