S55 owners—this is where airflow, reliability, and real power come together.
Every VAC S55 cylinder head service is performed in-house in our state-of-the-art machine shop by our skilled engine builders and engineers.
Using Centroid 5-Axis CNC porting on the intake and exhaust ports and a Newen CNC multi-angle valve job, we increase airflow efficiency,
improve top-end power, and create the headroom needed for higher boost and sustained track use.
All VAC cylinder head services are performed on existing customer cores. This requires the customer's core to be supplied to VAC for servicing.
Average horsepower results (with proper tuning):
• Stage 1 typically supports 10–20 WHP gains on bolt-on setups, while improving consistency and long-term reliability
• Stage 3 commonly supports 30–50+ WHP gains on higher-boost or upgraded turbo builds, with stronger top-end pull and better power per pound of boost
On larger turbo or track-focused builds, benefits often include faster spool at the same boost, cooler EGTs, and increased tuning headroom.
Service Options & Pricing:
Stage 1 – $1,299.95
• Valve guides*
• Valve seals
• CNC multi-angle valve job
• Resurfaced mating surface
• Complete assembly
Stage 3 – $4,799.95
• 5-Axis CNC porting (intake & exhaust)
• Performance valves
• Performance springs
• Performance retainers
• Valve guides*
• Valve seals
• CNC multi-angle valve job
• Resurfaced mating surface
• Complete assembly
*Includes valve guide labor costs. If new valve guides are required, an additional charge will be added.
Power is airflow. Reliability is precision. This is how you unlock both.