Power Driven’s Stage 1 CNC-Ported Towing Cylinder Head for 1989-1998 12v Cummins features a new aftermarket casting that is surfaced in-house to OEM specifications using state-of-the-art equipment to ensure reliable head gasket sealing. These heads receive Power Driven’s Towing Performance port job and enlarged pushrod holes for better clearance and improved oil drain-back. In addition, every CNC-ported Power Driven 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 to ensure optimal valve sealing. The head is then assembled by our expert technicians.

This head is available in 4 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, 60-lb. 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, 60-lb. valve springs, and chromoly retainers and comes fully assembled.

The Power Driven 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, resulting in 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 excellently 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.

The Power Driven Stage 1 CNC-Ported Towing Cylinder Head is compatible with:

*May not work for all builds due to other engine/vehicle modifications.