Valve Spring DataSaddle Pressure (Assembled) - 38kgLoad - 100kg@12.5mm Max. lifting height - up to 13mmMade of chrome-silicon steel SAE9254-VOuter 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: 16.20mm10 pcs. of external springs10 pcs. of internal springsDue to this set, there is a risk of valve vibration and possible engine failure is minimized. Recommended for engines with stock and racing camshafts and revolutions above 7,500 rpm.