Upgrading Your 6.0L Powerstroke: CNC Fab Stage 1 O-Ringed Cylinder Heads (18mm vs. 20mm)
If you own a Ford 6.0L Powerstroke diesel, you already know one of the biggest (and most dreaded) issues they face: blown head gaskets and cracked factory cylinder heads.
Whether you are rebuilding after a head gasket failure or bulletproofing your engine for peace of mind, high quality replacement cylinder heads are the most critical investment you can make.
CNC Fabrication offers two Stage 1 O-ringed cylinder head sets designed specifically to solve factory design flaws:
Why Factory 6.0L Powerstroke Heads Fail
Factory Ford 6.0L cylinder heads were prone to two main failure points:
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Thin Castings: OEM castings tend to flex under high boost and cylinder pressure, leading to microscopic cracks between the valve seats and coolant passages.
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Blown Head Gaskets: Under heavy loads, tuned performance, or high boost, factory TTY (torque-to-yield) head bolts stretch, allowing combustion pressures to bypass the multi-layer steel (MLS) head gasket.
What Makes the CNC Fab Stage 1 Heads Different?
Rather than reconditioning old, tired, stressed factory heads, CNC Fabrication builds these Stage 1 sets using new upgraded castings paired with precision machining and expert assembly.
Key Engineering Features:
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O-Ringed Protection: Every head is precision machined with an O-ring groove around each cylinder. The steel O-ring presses directly into the head gasket fire ring, creating a localized mechanical seal that prevents combustion gas blow-by, even under high boost levels.
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Upgraded Heavy-Duty Castings: Additional material is strategically added in those zones where cracks tend to occur around the valve seats and coolant jacket walls.
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Sunnen Precision Machining: Built in-house using industry leading Sunnen seat and guide machinery to maintain strict tolerances exceeding factory specs.
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100% Brand New Valvetrain Parts: Includes all new intake and exhaust valves, hardened valve seats, heavy duty springs, retainers, keepers, and valve stem seals.
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Vacuum Tested: Every head undergoes vacuum testing to ensure 100% airtight valve seat sealing before leaving the shop.
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No Core Required: You buy these heads outright, no hassle with core deposits, core returns, or shipping heavy, old parts back.
18mm vs. 20mm Dowels: Which Set Do You Need?
Ford updated the cylinder head locator dowel pin size mid-way through the 6.0L production run. Choosing the correct set comes down to your block's dowel size:
|
Feature |
18mm Stage 1 Set (SKU 421020) |
20mm Stage 1 Set (SKU 421023) |
|
Dowel Pin Size |
18mm |
20mm |
|
Fits Model Years |
2003 to Early 2006 |
Late 2006 to 2007 |
|
Typical Engine Build Dates |
Prior to 01/16/2006 |
01/16/2006 and later |
|
Product Link |
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If your engine block was built during the 2006 transition period, be sure to double check your current cylinder head dowel size or block build date before ordering to ensure a seamless fit.
Peace of Mind
If you are replacing head gaskets or doing a full engine rebuild on a 6.0L Powerstroke, installing a set of CNC Fabrication O-Ringed Stage 1 Cylinder Heads eliminates the root causes of head gasket failure. Paired with ARP head studs, these heads give your diesel engine the strength and durability it needs for daily driving, heavy towing, or high horsepower street builds.