Power Driven Diesel 5.9 Cummins Stage 1 CNC Towing Port Cylinder Head | 1989-1998 Dodge Cummins 5.9L

Power Driven Diesel’s 12v Cummins Stage 1 CNC Towing Port Cylinder Head features a new aftermarket casting that is surfaced to OEM specifications in-house using state-of-the-art equipment to ensure reliable head gasket sealing. These heads receive Power Driven Diesel’s Towing Performance port job as well as enlarged pushrod holes for better clearance and improved oil drain-back. In addition, every CNC ported PDD cylinder head is machined for compatibility with our Doweled Batwing Rocker Pedestals. After porting, valve and seat work is performed to optimize low-lift flow and swirl as well as ensuring optimal valve sealing. The head is then assembled by our expert technicians.

This head is available in four options:

• The “No Valve Springs” option includes OEM quality valves and OEM Top-Hat style seals, but no valve springs or retainers for customers who have already invested in high-performance valvetrain components and wish to reuse them.
• The “Loaded” option includes OEM quality valves, OEM Top-Hat style seals, 60lb Valve Springs, and Chromoly Retainers and comes fully assembled.
• The “O-Ringed, No Valve Springs” option is O-ringed to provide the ultimate seal possible with an OEM-style head gasket. This head includes OEM quality valves and OEM Top-Hat style seals, but no valve springs or retainers for customers who have already invested in high-performance valvetrain components and wish to reuse them.
• The “O-Ringed, Loaded” option is O-ringed to provide the ultimate seal possible with an OEM-style head gasket. This head includes OEM quality valves, OEM Top-Hat style seals, 60lb Valve Springs, and Chromoly Retainers and comes fully assembled.

The Power Driven Diesel Towing Performance port is a mild CNC port job that enhances intake swirl and exhaust flow while maintaining full water jacket thickness to retain stock-like reliability in the casting. By enhancing both swirl and exhaust flow, these cylinder heads produce higher fuel economy and reduced EGT compared to stock cylinder heads. On our SuperFlow 1020 test bench, this port produced a 31% increase on the intake and a 28% increase on the exhaust. Testing also revealed a 22% swirl increase, with a corresponding maximum intake flow of 172 CFM and peak exhaust flow measuring 178 CFM at 28″.

In real-world testing, the higher swirl and increased flow from this ported head slightly raised engine efficiency and peak power performance with resulting lower EGT readings compared to the stock cylinder head. Due to the higher port velocity and nearly stock port volume, these cylinder heads gain power/torque everywhere in the RPM range. These towing cylinder heads work excellent with mild or stock engines, especially applications with the stock camshaft or mild aftermarket upgraded cams. If you tow for a living, or use your Cummins to haul, this is the most reliable and best cylinder head for your application.