PRC 227cc CNC Ported LS Cylinder Heads

Current Stock:

Precision Race Components All New Cylinder Head Castings Completed With 227cc Runners For stock cubic inch LS1/LS2 applications.


  • 227cc Fully CNC Ported Intake Runners
  • 84cc Fully CNC Ported Exhaust Runners
  • Small Bore Chambers For Increased Horsepower & Torque+
  • PRC Platinum Spring Kit Rated To .650" Lift
  • 62cc or 68cc CNC Machined Chambers (Please notate choice in order notes)
  • 2.06" Intake / 1.60" Stainless Valves
  • Factory Rocker Friendly!!*

The all new 227cc cylinder head is finally available for customers looking for the pinnacle of LS cathedral port performance.  Now is your chance to own the same cylinder head that currently holds the fastest stock bottom end heads / cam record!  The new 227cc port has been flow bench tested to flow well over 325cfm & can support everything from smaller camshaft street engines all the way to all our race engines.  Engine dyno testing has shown these cylinder heads support over 650 flywheel horsepower in 408cid applications.

Flow Data:

4.00" Flow Plate - No Exhaust Pipe


Intake Flow 


 Exhaust Flow



 68 cfm


 56 cfm



 145 cfm


 115 cfm



 210 cfm


 167 cfm



 261 cfm


 202 cfm



 300 cfm


 219 cfm



 322 cfm


 238 cfm



 331 cfm


 236 cfm







*All aftermarket cylinder heads feature bronze guides. Stock rocker arms will cause increased guide wear in applications over .600" lift.  Roller rockers can help to reduce this wear.