SI manufactures a variety of valves for applications that range from racing and high performance street use to diesel, motorcycle and power sports use. In addition to the cataloged applications, SI can custom manufacture valves to customer specifications. Our lineup includes:
Manufactured from premium race-proven stainless steel alloys, most intake valves are made of EV8 and exhaust valves from EV16 material (also employed for intake valves in high combustion pressure environments). Features include hardened Stellite tips, chromed stems and swirl-polished heads. They are excellent for use in high performance street and most racing applications.
Ideally suited for high combustion pressure and high temperature applications, SI’s Silver Line Inconel valves provide racewinning reliability. They’re manufactured from a nickel-chromium-based superalloy and precision made to exacting tolerances. They feature hardened Stellite tips, hardchromed stems and swirl-polishing. Recommended for highly boosted supercharged, turbocharged or nitrous oxide applications.
Excellent for high RPM applications where valve weight is an important consideration, SI’s Silver Line Titanium valves are manufactured from a race-proven titanium alloys (6AL4V intake and 6242 exhaust) and feature one-piece forgings. They are available in a variety of finishes, including the popular DLC (diamond like coating).
Engineered for street applications, these stainless steel valves have a special coating that serves to improve heat transfer and combat the problems associated with unleaded gasoline. This translates into a significant improvement in service life. These high performance valves also feature Stellite tips and are swirl-polished.
Designed for budget rebuilds, SI’s Seat Saver OEM replacement valves feature an .030” oversized head that facilitates machining the factory seats as opposed to requiring the installation of new seats. All other dimensions are stock for compatibility with the OEM
guides. They are manufactured from stainless steel and available for many popular applications.
SI maintains an inventory of popular aluminum and titanium valve spring retainers and can custom manufacture them to customer specifications.
Our guides are manufactured in-house using a proprietary manganese-bronze alloy that is fortified using hard filament-shaped particles to enhance wear characteristics. It has exceptional heat transfer capabilities and is compatible with all contemporary valve stem finishes.
We have you covered with a wide variety of seals manufactured employing Viton, Teflon and rubber with a metal cladding. Viton is noted for its ability to withstand high temperature environments.
Available in various sizes and materials to suit your application. They are manufactured in-house using U.S.-sourced chromoly, ductile iron and MoldStar 90™ materials. These fine grain structure alloys provide greater heat transfer than lesser quality seats.
Available for both o.d. (cup) and i.d. (locator) valve spring seating applications, that are available in chromoly, ductile iron, MoldStar 90 and other materials. In addition to shelf-stock part numbers, SI can custom manufacture cups and locators to your specifications.