PRC LS3 As-Cast 257cc Cylinder Heads, .660 Spring Package
Fully assembled PRC LS3 as-cast aftermarket cylinder heads with CNC-machined chambers and guides.
- 257cc as-cast intake runners
- 68cc chambers
- 13-degree valve angle
- 2.170-inch hollow-stem stainless intake valves
- 1.600-inch stainless exhaust valves
- TSP .660-inch PAC dual springs with titanium retainers
- Factory rocker compatible
- Extra-thick deck surface for power-adder applications
Fitment: LS3, L92, L99, LSA, LS9, and related Gen 4 rectangle-port engines. Verify compression, piston-to-valve clearance, pushrod length, and intake-manifold compatibility before installation.
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