Description:
Valve seat forming is a critical step in several ways. Maximum airflow is possible with fully developed seat shapes, contours and widths. Maximum power and torque output is the results of the most effective seat dimensions. Probably most important to the consumer is a combination of the above factors along with maximum valve seat life and durability. Without effective sealing at the valve seats the engine will never make the power and torque it has the potential to. A good cylinder head is only as good as the sum of its valve seat concentricity and sealing abilitiy over the longest possible life span. Valve seat seal is the top ends equivalent of piston ring seal in properly prepared cylinder bores.
These two items together provide the compression pressure to make power while minimising parasitic blowby of combustion chamber gases.