Valve dataPressure at valve seat - 38kgLoad - 100kg@12.5mmMaximum stroke - up to 13mmMade of SAE9254-V chrome-silicon steel Outer valve outer diameter: 30.50mm Outer valve inner diameter: 23.20mm Inner valve outer diameter: 21.20mmInner diameter internal valve: 16.20 mm 10 pcs. external valves 10 pcs. internal valves Fits 5-cylinder 10V Audi / VW 2.5TDi engines. Thanks to this set, the risk of valve vibration and possible engine failure is minimized. Recommended for engines with factory and racing camshafts and revolutions above 7500 rpm