Cylinder Head Work / Upgrades

Available for all Honda K, B, H and D series engines




CPL Racing offer a full cylinder head porting service for mild road cars/track day cars through to a full on race car.  These ported heads are used in race winning rally, endurance, circuit racing and drag racing.  UPDATE!  CPL RACING ARE NOW OFFERING CNC PORTED HEADS FOR SOME APPLICATIONS, please see the CNC Ported Cylinder Heads page on our website for more information.



CPL Valve guides.

CPL’s own design of valve guides are manufactured using profiles derived from many hours of flow-bench testing, in order to optimise flowing profiles.  The guides are manufactured from the finest aerospace material which enables us to run much closer valve to guide clearances, ensuring that the valve returns true to the valve seat and creating more vacuum in the inlet port.

For added piece of mind these valve guides have been tested in CPL’s own road and race vehicles to ensure longevity.  


Multi-Angle Valve Seats

Through a process of trial and error utilizing  both our flow-bench and dyno we have optimised valve seat profiles to suit many applications.  In conjunction with valve guide and port shapes we have been able to achieve highly improved flowing from cylinder heads for both naturally aspirated and forced induction applications.  Our multi angle/radius valve seat profiles are machined using the latest CNC technology


Port Velocity

It is highly important to consider the speed of the airflow through the ports, as well as the flow itself.  At CPL Racing we have the ability to measure port velocity in addition to flow on our in-house  Superflow 1050 computerised flow bench.

If you are interested in cylinder head upgrades please email us at with details of your engine and requirements and we will be happy to quote by return.

flow bench

Why shop with us?

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  • Longest serving official Hondata dealer in Europe
  • On site dedicated electronics engineer
  • Quickest turnaround times
  • Technical support
  • All Hondata products stocked
  • Full on-site dyno tuning service
  • ECU testing

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