Cummins 5.9 12 Valve Ported & Polished Cylinder Head w/ Fire Ring Grooves

Fits: 1989-1998 12V Cummins

Item Type: Indsutrial Injection 5.9 12 Valve Ported & Polished Cylinder Head w/ Fire Ring Grooves

Brand: Industrial Injection

Part Number: PDM-12VSTH

Core Charge of $700.00 In Addition to Listed Price

Features:

• CNC Ported Cylinder Head
• New Stainless Steel Valves
• High Strength Alloy Valve Guides
• Drilled & Tapped Coolant Freeze Plugs In Head
• Fire Ringed Head
• Industrial Injection 150lb Valve Springs

 Core Charge-$700.00 on top of listed price

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

Note: Fire Ring Head Gasket sold separately.

The Build Process:

Heads are 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; air flow 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 to 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 preformed 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 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 exact size using a diamond honing mandrel. Diamond abrasives allow for consistency of size, surface finish, and bore geometry with no variation from guide to guide. The guide size is then verified using a valve guide bore gauge. Next the head is treated to 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 our berco milling machine we 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.

*Fire ring gasket not included. Please see related products below