... passed ISO 9001 and ISO/TS 16949. 2. our engine valve kind is complete ,the quality is frist-class, the price ... normal, good material: INLET VALVE IS SUH3(4Cr9Si2) ; EXHAUST VALVE IS SUH35(21-4N), normal material: INLET VALVE IS SUH1(40Cr) ; EXHAUST VALVE IS SUH3(4Cr9Si2 ... ,VOLKSWAGEN AND SO ON. 4. We have all kinds of valve techniques, entire material valves, double mttal friction welding , small ...