12 Valve Cummins Parts — Cylinder Heads, Gaskets & Engine Components
The 12 Valve Cummins is one of the most sought-after diesel platforms ever built — mechanically simple, enormously strong, and highly tunable. Head work and valve train upgrades unlock the full potential of this engine for towing, sled pulling, and street performance builds.
O-ringed cylinder heads are a proven solution for high-boost 12 Valve builds where stock head gasket retention becomes the limiting factor. This is a standard upgrade on any serious 5.9L 12V performance build.
Factory 12 Valve valve springs were not designed for the lift and boost levels common in performance builds. Upgraded springs prevent float and maintain power at the RPM range modified 12V engines reach.
Whether this is a daily tow rig or a dedicated performance build, parts here are selected for the demands the 12 Valve actually faces — not just catalog specs.








