Porsche Cylinder Head Rebuilding Services

LN Engineering’s rebuilt Porsche cylinder heads benefit from decades of specialized experience and thousands of Porsche cylinder heads rebuilt to date. Our cylinder head team has extensive experience with M96/M97 Boxster, Cayman, and 911 cylinder heads as well as aircooled Porsche applications. We have also rebuilt cylinder heads for other European makes including Volkswagen/Audi, BMW, and Mercedes-Benz. Every cylinder head is inspected, with components tested, reconditioned, or replaced as required. Our standard rebuild process includes a multi-angle Serdi valve job, Viton valve stem seals, and CBN machining of critical sealing surfaces to achieve the proper finish. Valve seats, valve guides, valve springs, retainers, and locks are inspected and replaced when worn. M96/M97 cylinder heads are pressure tested, and all completed cylinder heads are vacuum tested after final assembly as part of our quality-control process.

What Is Included in a Porsche Cylinder Head Rebuild?

• Initial inspection for cracks, warpage, and other damage
• Cleaning and preparation of cylinder head castings and components
• Valve, valve guide, valve seat, spring, retainer, and lock inspection
• Valve guide replacement and honing when required
• Precision multi-angle Serdi valve seat machining
• CBN resurfacing of critical sealing surfaces
• New Viton valve stem seals
• Pressure testing of M96/M97 cylinder heads
• Final vacuum testing after assembly
• Performance machining such as CNC porting, hand finishing, twin-plug machining, or other application-specific services where appropriate
• Optional performance valve, valve spring, and valve retainer packages
• Brand-new billet cylinder heads for select aircooled Porsche applications

Cylinder head rebuilding is one part of LN Engineering’s complete Porsche engine machine shop services, which also include engine case machining, cylinder reconditioning, connecting rod work, crankshaft services, balancing, and precision inspection.

Aircooled and Watercooled Porsche Cylinder Heads

We rebuild both aircooled and watercooled Porsche cylinder heads. Aircooled applications can require guide and seat work, resurfacing, performance valve-train upgrades, CNC or conventional porting, twin-plug machining, or other corrective work depending on the engine and intended use. Watercooled Porsche cylinder heads, including M96 and M97 applications, require careful inspection for cracking, warpage, guide wear, seat condition, and sealing-surface integrity before machining and assembly. We can also evaluate cylinder heads from other European performance applications, including Volkswagen/Audi, BMW, and Mercedes-Benz, when the required work fits our machining capabilities.

For track or race applications, additional component replacement or upgrades may be appropriate based on the engine, operating conditions, and intended service. The correct cylinder head repair plan should be based on inspection and measurement rather than replacing parts unnecessarily or machining components without first establishing their condition.

CNC-Ported & Billet Porsche Cylinder Heads

In addition to conventional cylinder head rebuilding, LN Engineering offers performance cylinder head services for Porsche applications, including CNC porting on our Haas UMC-1000 5-Axis Machining Center. CNC porting allows the intake and exhaust ports to be machined consistently from one port to the next using proven digital geometry, helping improve repeatability while reducing the variation that can occur with fully hand-shaped ports. Final hand finishing and application-specific valve-seat work can be incorporated where required by the build.

For select aircooled Porsche engines, LN Engineering also offers brand-new billet cylinder heads. These heads provide an alternative to rebuilding decades-old castings when the project calls for a new performance-oriented foundation. Billet heads can be paired with the appropriate machining, valve-train components, chamber work, and port configuration for the intended engine combination.

Whether the goal is restoring a stock Porsche cylinder head, repairing a damaged casting, or building a higher-performance aircooled or watercooled Porsche engine, the final specification should be matched to the engine’s displacement, compression ratio, camshaft, intake and exhaust system, intended rpm range, and use.

Quality

For decades, Wally Werner built a reputation in the Chicagoland area for high-quality cylinder head machining and engine rebuilding, serving Porsche dealerships and independent repair shops through Werner Machine Ltd. before joining LN Engineering. His experience has played an important role in developing the processes and standards used in our cylinder head department.

Wally has since passed that knowledge on to the next generation at LN Engineering, with Cody and Matt now handling day-to-day operations in the cylinder head shop. They continue to follow the same emphasis on careful inspection, precise machining, repeatable processes, and quality control that has defined our cylinder head work for decades. This transition allows us to preserve that experience while continuing to expand our Porsche cylinder head rebuilding, CNC porting, and performance machining capabilities.

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