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Cylinder Head


Model # 13476858 | Mfg # 18-4504
Ships directly from the vendor
  • Aluminum cylinder heads sold in pairs only or 454 & 502 cu.In big-block GM applications.
  • Custom engraved with Sierra High-Performance logo
  • 320 cc intake runner/119cc exhaust runner
  • 2.25 intake/1.88 exhaust stainless steel valves
  • 5 angle valve seat cut
  • Up to 65HP increase over OE cylinder heads
  • Suitable for use on Mark IV, Gen V, & Gen VI GM blocks. Must use correct corresponding head gaskets
  • Std. BBC 7/16" rocker studs and 3/8" diameter pushrod guideplates18-4506
  • Rectangle intake ports GUIDE PLATES
  • Use on factory non-adjustable valve train applications require adjustable rocker arm assemblies such as Sierra's 18-4507
  • Uses Sierra 18-4506 guide plates to utilize factory 5/16" pushrods

Cylinder Head

Type Heads

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