Rohnert Park Auto Repair

What is Cylinder Head Porting?

Cylinder head porting is the action of modifying the intake and exhaust ports of an internal combustion engine that then results in an improvement of the quantity of airflow. This alone creates more power because more air in equals more power out. In heads that have not been ported, incoming air passes up and over obstructions. This means less air gets through resulting in less power capabilities. Cylinder head port matching provides a direct path, removing the obstructions from intake to head. The cylinder head porting job can be applied to any engine. There are a variety of areas within the cylinder head that we attend to in order to meet your specific performance goals. Some example of these include:

  • Exhaust Ports: We can shave material here where the highest velocity air is found to be leaving the cylinder. Then our experts conduct port matching to ensure the diameter between the two components stays the same.
  • Inlet Ports: Material can be shaved in the inlet ports to relieve them of unwanted metal casting.
  • Valve Throat Pocket: We smooth and widen the valve throat pocket to provide the most efficient air flow.
  • Valve Seat: Modification to improve the volumetric efficiency of the engine.
  • Combustion Chamber: Provide a polished finish allowing smooth flow of the air fuel mixture out of the cylinder and then into the exhaust manifold.

When modifications are complete the head is then tested on an air flow bench to measure the volumetric flow rate. Once everything tests properly, you have yourself additional horsepower!

Cylinder head porting adds both torque and horsepower, although the amount varies vehicle to vehicle. Generally, it adds between 20-30 hp but for a more precise answer give our machine shop a call. It depends on your vehicle and the specific type of head porting we complete for your vehicle.  One additional benefit that customers love is that cylinder head porting generates better fuel atomization that leads to better fuel economy. Looking to experience more power? More torque? Better fuel economy? Cylinder head porting might be the vehicle modification you’ve been searching for.

Give RPM Engines and Machine a call, today! Or stop by with your vehicle and let’s talk about your goals. We look forward to seeing you soon!


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