Valve dataPressure with seat installed - 38kgLoad - 100kg@12.5mm Max. extension - up to 13mmMade of chrome-silicon SAE9254-V steelOuter diameter of the outer spring: 30.50mmInner diameter of the outer spring: 23.20mmOuter diameter of the inner spring: 21.20mmInner diameter of the inner spring: 16.20mm8 pcs. of external springs8 pcs. of internal springsFits for Audi / VW 1.9 engines TDi 8V (not PD/CR). This set minimizes the risk of valve vibration and possible engine failure. Recommended for engines with stock and racing camshafts and revolutions above 7,500 rpm.