Speedmaster PCE281.1455 LS1 LS2 LS6 As-Cast Aluminum Bare Cylinder Head 210cc / 62cc Cathedral Port

The Speedmaster PCE281.1455 is an as-cast aluminum bare cylinder head engineered for GM Gen III/IV LS-series engines, including LS1, LS2, and LS6 applications. Built using Speedmaster's T6 heat-treated gravity die-cast process, this head delivers a more uniform and robust casting that serves as a reliable foundation for street/strip performance builds.

Featuring a 210cc cathedral-port intake runner and a 62cc combustion chamber, this head is designed to improve airflow and power delivery across the rpm range compared to stock GM castings. The as-cast design is ideal for entry-level performance builds and offers plenty of material for future upgrades to higher-horsepower applications.

Key Specifications:

• Intake Runner Volume: 210cc (Cathedral Port)
• Combustion Chamber Volume: 62cc
• Intake Valve Diameter: 2.020 in.
• Exhaust Valve Diameter: 1.550 in.
• Intake Valve Angle: 15°
• Exhaust Valve Angle: 15°
• Intake Port Shape: Cathedral
• Exhaust Port Shape: Oval
• Cylinder Head Style: Bare (no valvetrain components included)
• Cylinder Head Material: Cast Aluminum
• Cylinder Head Finish: Natural
• Valve Cover Mounting Style: Perimeter Bolt
• Accessory Bolt Holes: Pre-drilled to OEM pattern

Key Features:

• Bronze valve guides for durability and wear resistance
• CNC-finished mating faces and bolt holes for precision fitment
• T6 heat-treated gravity die-cast aluminum construction
• OEM accessory bolt patterns retained
• Machined for screw-in studs and guide plates
• Flame-hardened valve seats compatible with all fuel types
• Ample material for boring or upgrading to larger valve sizes

Hardware Notes:

• LS1/LS2/LS6 intake manifold O-ring seal: GM PN# 12533587
• Exhaust (non-LS7) MLS header gasket: GM PN# 12901125
• Compatible head bolt kit: Speedmaster SM2464 or ARP #134-3610 (bolts) / ARP #23-4317 (12pt studs)
• Torque specs: 11mm bolts/studs to 65 lb-ft; 8mm bolts/studs to 20 lb-ft (use high-pressure moly lubricant)

Sold individually. No valves, springs, retainers, locks, rocker arms, pushrods, or guideplates are included. This is a bare head intended for builders who will supply their own valvetrain components.