1989-1998 Cummins Performance Head (PDM-12VSTH)

Fully CNC-ported performance cylinder head for 1989-1998 Dodge 5.9L 12V Cummins engines. Built for the daily-driver who wants real airflow gains — bolt-on ready with new stainless valves, upgraded guides, 150 lb valve springs, and fire-ring grooves machined for high-cylinder-pressure builds.

Porting is done on a 5-axis CNC porting machine with CAD/CAM software developed specifically for cylinder head work. Every port flows the same, which balances cylinder-to-cylinder power output and makes tuning predictable. After CNC, Industrial Injection hand-blends each port to clean up the transitions.

The head is given a multi-angle valve job on a Serdi 100 seat machine, milled flat with CBN tooling for MLS-compatible surface finish, then jet-washed and assembled with new performance valve springs and seals before it ships.

• 5-Axis CNC Ported & Hand-Blended
• New Stainless Steel Valves with Nitrate Coating
• Heat-Treated Alloy Valve Guides (Rockwell 22)
• Steel Freeze Plugs (Replaces Leak-Prone Aluminum)
• Fire Ring Grooves Machined for Custom Fire Ring Head Gasket
• 150 lb Performance Valve Springs Installed
• Multi-Angle Valve Job (Serdi 100)
• MLS-Compatible Surface Finish
• Bolt-On Ready
• Part Number: PDM-12VSTH

• Fire ring head gasket is sold separately (PDM-4068C) — required to take advantage of the fire-ring grooves.
• Head studs (not bolts) are required on any fire-ringed build to hold clamping load.
• Comes assembled but does not include the rocker assembly or pushrods — reuse from your existing head.