7. 8. 2017 Sodium-filled exhaust valves The technology of hollow and sodium-filled exhaust valves is used in motorsport and in high-performance engines. The sodium filling prevents overheating of the valves and allows the engine to operate at higher exhaust gas temperatures. Additional info File type: PNGFile size: 997 KBDimensions: 800 × 800 pxPublished: 7. 8. 2017