CHE – VALVE GUIDES
CHE Precision searched the world over till we finally discovered a specialty foundry that was willing to make the extra effort and go that extra mile to pour the rare, high grade materials necessary to accommodate the custom designed blends that meet CHE specifications. Our commitment to “Limited Batch Processing” and continuous quality assurance inspection, as well as dedicated attention to intricate detail, has put CHE in the position to provide the finest parts available on the market, including our specialty bronze alloys.
Our product line consists of a wide variety of sizes and configurations. We have the ability to manufacture any type of guide needed to fit your specific, individual application. These quality guides are made from severe duty bronze and are designed for long life in “after-market” cylinder heads.
For the serious racer, CHE Precision offers an “XP” (Extra Precision) series valve guide, which is used by the industry’s top racing teams. These are made from a special formulation of HT Bronze, developed from over 25 years of extensive research and experience in the racing industry. This particular bronze was specifically developed to provide extended wear properties and extraordinary heat dissipation.
The ID (Internal Diameter) is a 10Ra, or better, finished with a burnished surface. All of the “XP” guides are OD (Outer Diameter) ground by locating the guides in their ID. The “XP” series is guaranteed to be concentric to within 0.0005 inch or better. What we’re talking about here is a most amazing, state of the art product that has been carefully designed to be the perfect combination of quality materials and precision craftsmanship, unmatched anywhere throughout the industry.
A worn guide can be removed from the cylinder head and a new guide installed with minimal work, usually by just guide honing and kissing the valve seat with a fresh valve job. CHE also manufactures steel valve guides primarily used in the drag racing market (Top Fuel).
Custom and Specialty guides are, of course, always available, and manufactured to your exact specifications. We’re happy to rise to the occasion of serving any particular need, and will gladly help with any research or development to do so. Our number 1 job is to be there, whenever called upon, to serve our customers, providing answers to questions, solving unique problems or making newly created applications available to our friends and clients.
CHE – VALVE SEATS
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.
This special formula was also specifically designed to minimize valve “bounce,” associated with high RPM (above 8000) and with radical cam grinds lacking a sufficient closing ramp. The thermal conductivity of CA-18 is vastly superior to the ductile iron seat in the casting of “after-market” cylinder heads.
Tolerances can be held at ±0.0001 inch in diameter and ±0.0005 inch in thickness. Normal diameter sizes range from 1.3000 to 3.0000 inch. Any angle, multiple angles, radius or multiple radii can be machined inside the valve seat.
X-274: CHE Precision formulated X-274, in response to unique circumstances incurred while dealing with the specific applications of exhaust seats. This material was custom designed to resist the extreme exhaust temperatures associated with auto racing engines. The thermal conductivity is 15% greater than that of beryllium copper, thus greatly reducing the temperature of the exhaust valve. This remarkable formula was also designed to minimize valve “bounce,” associated with high RPM (above 8000) and with radical cam grinds lacking a sufficient closing ramp.
The expansion rates of this seat are also similar to that of the aluminum used in the casting of the “after-market” heads. Tolerances can be held at ±0.0001 inch in diameter and ±0.0005 inch in thickness. Normal diameter sizes range from 1.0000 to 2.2000 inch. Any angle, multiple angles, radius or multiple radii can be machined inside the valve seat.
CHE – LIFTER BORE BUSHINGS
Lifter bore bushings that last 2-4 times longer than our competitors. As with all CHE products if you are searching for precision, quality and long lasting performance, you will not find a better product anywhere. CHE Performance understands racing needs and can manufacture a lifter bore bushing to your specifications.
CHE – SPRING RETAINERS
Our racing designed titanium spring retainers are the lightest in the industry and have proven to have less valve bounce at high RPM. This amazing achievement has been accomplished without sacrificing part longevity.
CHE – LS SERIES ROCKER ARMS
CHE have teamed up with the industries best engine builders to come up with an innovative improvement on the factory production rockers. One issue roller rockers inherently have is they are prone to failure at high RPM. By replacing the roller bearings assembly with CHE’s proprietary material bushing, this will allow the rocker arm to survive the extreme rigors of high RPM race engines
New – CHE – LS SERIES ROCKER ARM TRUNNION KIT
The trunnion and bushing conversion kits require onl6y the use of snap ring pliers and assembly lube or oil to assemble, and are made from materials that we have been using on our trunnion conversions since February 2006. They are made from our proprietary bushing and valve guide material that CHE have been using for over 30 years. The bushings are designed to slip fit onto the trunnion and into the rocker and therefore do not need the use of special tools or a press. This design will increase the amount of useable wear surface, as the bushings will continue to rotate in the rockers and around the trunnion. Our oiling design is the same as it always has been, grooves that are machined in a spiral pattern around the bushing on the OD and ID.
CHE – SPRING CUPS & BASES
All steel spring cups and bases receive heat treatment, which gives long lasting wear.