Page 685 - 2021 Sierra Catalog
P. 685
667
CYLINDER HEAD ASSEMBLIES
All cylinder heads are new castings and complete assemblies with new stainless steel valves, hardened steel exhaust seats, valve springs, valve locks and retainers.
All GM cylinder heads utilize high performance screw-in rocker arm studs in place of factory press in rocker arm studs.
18-4485HP
CYLINDER HEAD ASSEMBLY
Fits: Mid GM small block 5.7L high performance.
Completely assembled with revised runner and combustion chambers. Add 30hp to stock motor with no additional modifications.
18-4486HP
CYLINDER HEAD ASSEMBLY
Fits:Vortec GM small block 5.7L high performance
Completely assembled with revised runner and combustion chambers. Add 30hp to stock motor with no additional modifications.
18-4484HP
CYLINDER HEAD ASSEMBLY
Fits: Early GM small block 5.7L high-performance Completely assembled with revised runner and combus- tion chambers. Add 30hp to stock motor with no additional modifications.
18-4493HP
CYLINDER HEAD
Fits: Big-block GM cast iron performance
INTERNAL ENGINE COMPONENTS — Cylinder Heads
