PRC 227cc CNC Ported Small Bore 3.9"-4" Cylinder Heads

Precision Race Components all new cylinder head castings completed with 227cc runners. For stock cubic inch LS1/LS2 applications requiring smaller chambers for extra compression MADE IN THE USA!! CAST IN THE USA!! MACHINED IN THE USA!! Features:  227cc Fully CNC Ported Intake Runners 84cc Fully CNC Ported Exhaust Runners Small Bore Chambers For Increased Horsepower & Torque+ SPECIFICALLY DESIGNED FOR 3.9"-4" BORE APPLICATIONS TSP .660 Spring Kit w/ PAC Valve Springs & Titanium Retainers 62cc CNC Machined Chambers CHE Bronze Guides 2.065" Hollow Stem Intake Valves / 1.600" Stainless Exhaust 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 over 320cfm & can support everything from smalle