Hollow point

A little-known fact about the Stinger’s twin-turbo engine is that it’s the first V6 to feature a sodium-filled stem and head on the exhaust valve. Sodium-filled valve stems have been around for decades, the tech helping them dissipate heat and stay cooler. A solid valve in this engine would run in the mid-800ºc range; by sodium-filling both the stem and head, the operating temperature of the exhaust valve can drop as much as 200ºc, allowing for significant spark advance without having to worry about keeping valves cool.