Drag Racing Action- November 2004 Issue
Manufacturing High Tech Titanium Valves
By Sean Honan
Within the racing industry lies a number of secret treasures. Both large and small companies and individuals who perform quality work behind the scenes for race teams looking for the competitive edge. The tiny town of Thomasville, North Carolina might well be known for the furniture factories that dot the landscape, but it also is an unlikely place to find cutting edge valvetrain technology.
But in late 2003, Xceldyne Technologies, a direct manufacturer of titanium valves, packed up and relocated their headquarters across the country to Thomasville from Valencia, California, bringing with them the high-tech knowledge that has earned a partnership with many of the world's great race teams. With dedicated valvetrain machines, 80 employees and operating 24 hours a day, it didn't take long for Xceldyne to become comfortable within the North Carolina racing industry.
Xceldyne principal Ben McCabe explained, “It quickly became clear that this site provides us with an ideal home offering many benefits; a professional-looking site, easy access to the primary corridor (Interstate 85), close proximity to the future FedEx shipping hub in Greensboro, and neighbors who are already involved in the racing industry.”
One of those new neighbors is corporate partner CV Products, who recently announced that they’ve reached an agreement to become the U.S. sales and service representative for Xceldyne. CV Products is well known within the performance and racing industry and during its 15 years has become widely respected by racers for meeting the unique needs of professional engine builders and racers. Xceldyne has also teamed up with CV Products to become awards posting contingency sponsors of the NHRA for 2004.
With the ever-expanding use of large inch engines within drag racing, the need for a lightweight titanium valve is increasing as well. Larger valves carry with them an increased weight, which when coupled to rapid opening camshaft rates, can cause valvetrain problems. The lightweight afforded by the titanium material allows valvetrains to live in the brutal world of low elapsed times.
However, just turning down a bar of titanium into a valve shape isn’t the proper method to come up with an affordable and long-lasting product. Long before manufacturing begins, Xceldyne engineers are put to work utilizing the latest CAD software to come up with a design that will suit their customer’s needs.
The next step involves the creation of a computer-generated solid model, verifying the strength and integrity of the part long before it’s even made. From this computerized model, a rapid prototyping or Stereo Lithography Apparatus (SLA) process is used to create incredible three-dimensional models of custom components on a computer, which then "prints" the final product out of resin. Not only does this process save overall manufacturing and waiting time for a single component to be produced, but also resin models can be used for many testing functions prior to ordering a final production run. This can virtually eliminate the opportunity for design errors. Also small adjustments can be made to the overall design during development, thereby enabling production of variations of the part and enabling a customer to test multiple designs before producing a single titanium piece.
While some companies might start off with a titanium forging, Xceldyne utilizes a spun, or inertia welding process to attach the partially machined valve head and stem together. During this process, the two previously machined parts are fused together using state-of-the art equipment that uses inertia and friction to bond the two into one solid component. Once this "valve blank" is fused, it’s heat treated to alter the grain structure of the titanium through precision heating and cooling at varying temperatures, taking into account the properties of the alloys used and the end application (intake or exhaust). This process is so effective that when completed, inertia welded valves have been certified as having a better grain structure than a forged one-piece design.
CNC-machines then take over the undercut stage of valve stem shaping prior to Plasma Moly coating. Plasma Moly is then sprayed using proprietary technology and robotic guns to the surface of the rough valve. Specific sections of the valve are then further machined, leaving a coating of Moly remaining over only the desired stem areas. This protects the stem against the friction created by movement within the guide.
The head, stem and keeper grooves of the valve are now machined further, working more towards the final shape of the valve. Two types of valve tips are available, with one being a steel tip while the other, a ceramic-coated tip, is specifically designed for applications using lash caps. On ceramic tip valves, an extremely durable ceramic hard coating is applied to the valve tip to once again protect the titanium from friction caused by the use of a lash cap. Stem grinding is then finalized to established dimensions, all with tolerances of just .0002". The valve is then precision polished to create a flawless surface finish and reduce the opportunity for carbon buildup.
During final quality control, the valve is then measured with extremely accurate lasers inside of an environmentally controlled room where humidity, temperature and particle collection are constantly monitored and regulated. As a result, each customer is provided a certified inspection and highly detailed quality report for each valve manufactured.
“Even our most demanding customers have been impressed with the level of technology, personnel, equipment and most importantly service, we have to offer,” stated McCabe. “And now through our recent expansion and partnership with CV, we’re able to utilize their marketing, distribution and technical sales/support expertise in engine and valvetrain components. They also have long-standing relationships with engine builders and racers in virtually every market, and most importantly, place equal importance on customers at every level - from the professional ranks to the grassroots and local level.”
The move from California has also increased manufacturing square footage space that has enabled them to expand the product line from primarily just titanium valves, to now include titanium retainers, titanium and steel locks, valve guides, lash caps, valve and spring seats/cups.
"We’ve found that by being able to expand our product line within the valvetrain system, we now provide customers with a better product," Xceldyne technical representative Tom Malaska explained. "Our components are now specifically designed to work together, within the most minimal of tolerances and in the most demanding applications.” The same stringent processes and quality control steps that their valves go through are applied to their other valvetrain components as well.
Working closely with some of the elite teams in international motorsports, Xceldyne valvetrain components can be found in NHRA, IHRA, Formula One, NASCAR, CART, IRL, World Rally, Le Mans, APBA and many more. Like many others before them, when you’re able to build a reputation like this in the racing industry, it's tough to keep it a secret for very long.