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MTM510-323 - Mast Motorsports Cathedral Port 11 Degree,?245cc 6-Bolt Medium Bore CNC Assembled (4.000"-4.070" Bore), Single

This product may require vehicle validation(s) for proper fitment. Please contact us to confirm correct vehicle fitment and usage.

Availability: Special Order Item
Pricing: $1,424.95


• Designed for any new Gen IV 6.0L or 6.2L engine
including LS3, L99, L92, L76, LY6, LSA, and LS9
• Perfect for LS1 / LS6 stroked short blocks
• Available as packages for LS3 Camaro, Corvette, L99 Camaro, & L76 Pontiac G8
• Accepts Gen IV LS3 rockers with available rocker stands
• Works with any Cathedral Port intake manifold, including FAST.
• Uses a 2.165" intake valve and 1.600" exhaust valve
• Has a 245cc intake port
• Has a 70cc combustion chamber standard
• Has a deck thickness of .750

Each Mast Black Label cylinder head assembly includes:

•A fully CNC machined Mast Black Label aluminum cylinder head
• Mast micro finished .650 lift beehive valve springs
• Mast lightweight stainless steel intake & exhaust valves
• Mast lightweight steel retainers
• Mast machined locks
• • NOTE: Gaskets, valve covers, rocker arms and pushrods not included
• • NOTE: GM offset intake rocker arms required

Application List


Shipping Information

  • Item Requires Shipping
  • 30.0 lbs.

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