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

Fits

The Industrial Injection 5.9L 12V Cummins Street Heads are designed for the daily driver/weekend warrior in mind. Fully CNC ported heads complete and ready to bolt on.

The porting process performed uses a new 5 Axis CNC Cylinder Head Porting Machine with CAD/CAM software specifically designed for cylinder head porting. CNC porting brings unparalleled accuracy to head porting with each port flowing the same. This helps balance the power that each cylinder produces, making tuning easier. After the CNC process, Industrial Injection then hand blends each port to perfection.

Part Number:  PDM-12VSTH

• Porting process performed uses a new 5 Axis CNC Cylinder Head Porting Machine with CAD/CAM software specifically designed for cylinder head porting
• Highest quality upgraded stainless steel valves
• Heat Treated iron based valve guides are installed
• High-quality steel plugs 
• Custom fire ring head gasket which utilizes a radius cut steel fire ring to virtually eliminate head gasket failures while still allowing you to daily drive your vehicle with confidence in its longevity capabilities.
• Upgraded stainless steel valves with a nitrate coating
• Radius-cut steel fire ring to virtually eliminate head gasket failures
• Highest quality brand new performance 150lb valves springs

Heads are the first jet washed in a high-pressure spray cabinet to remove oil and dirt, then glass beaded to remove carbon. Next, they are checked by magnafluxing, (cast iron only) or pressure testing. They are visually inspected for defects that would make them unusable. Valve guides and seats are removed as needed for porting.

Port development is accomplished using a superflow 600 flow bench with a computer recording all flow measurements.
Many things are considered when designing a cylinder head Port; airflow is only one of the things to think about. Another major concern is port wall thickness.

Anyone can get a head to produce high flow numbers, but if doing so leaves the port wall too thin the casting will crack. High-performance Diesel heads are more prone to crack because of the thermal shock experienced by excessive intermittent or long-term exhaust temperatures.

The porting is then performed using a new 5 Axis CNC Cylinder Head Porting Machine with CAD/CAM software specifically designed for cylinder head porting. CNC porting brings unparalleled accuracy to head porting with each port flowing the same. This helps balance the power that each cylinder produces, making tuning easier.

New High Strength Alloy, Heat Treated iron-based valve guides are installed. These guides are heat treated to Rockwell 22 Scale, which produces the ultimate in wear resistance. This is far superior to the original guide material, including Bronze. The guide incorporates a spiral grove inside the guide to hold oil and aid the lubrication of the valve during engine operation.

Guides are then honed (not reamed) to the exact size using a diamond honing mandrel. Diamond abrasives allow for consistency of size, surface finish, and bore geometry with no variation from the guide to guide. The guide size is then verified using a valve guide bore gauge.

Next, the head is treated with a multi-angle valve job to help maximize the flow of air in and out of the head. This is accomplished using a Serdi 100 guide and seat machine. Serdi uses a solid carbide straight-shank pilot. When inserted into the valve guide, it simulates the real valve stem during the centering process. This guarantees the valve seat is finished for a perfect valve-to-seat match.

Using CBN or Diamond tooling the head is given a new surface. With an Industrial Injection Berco Milling Machine, they can control the surface finish to accommodate different head gasket types. For example, MLS head gaskets require a very smooth surface finish.

Finally, the head is jet-washed dried, and assembled with new valve seals and new performance valve springs.