CHE Manufactures it’s valve seats out of three primary materials: Ductile Iron, CA-18 and X-274. Each has it’s own unique and special purpose and application, in which it is best suited. The most commonly used of the three is the Hardened Ductile Iron Seat. CA-18 and X-274 compositions have been specifically designed to stand up to the arduous abuse constantly dealt out in the highly competitive and rigorous racing environment.
Although both of these custom created materials involve a larger initial investment, our satisfied customers all say they receive benefits well beyond the value of the extra expenditure. Benefits that have been drawn out of over 25 years of continual research and development, proving their worth on the field of battle, time and time again. Understandably, the patented composition of these two truly remarkable materials (CA-18 and X-274) is propriety information, known only to, and owned exclusively by, CHE Precision Inc.
Ductile Iron: This precision seat is first machined on a “Screw Machine,” then hardened to RC 32-38. After the heat-treating process, the valve seats are surface and OD (Outer Diameter) ground to ±0.0002 inch in diameter and ±0.001 inch in thickness. Normal diameter sizes range from 0.500 to 2.750 inch. Any angle, multiple angles, radius or multiple radii can be machined inside the valve seat.
CA-18: In order to meet the demands of certain, specific applications, CHE Precision rose to the occasion, and custom formulated CA-18. This material is primarily used for the manufacturing of “intake seats”. Intake valves and seats are continuously subjected to the dramatic alternating tortures of constant heating and cooling. The seat, therefore, needs to be manufactured with the built-in ability to stand up to this inconsistent thermal activity.