Saab: 1995 Saab 900 V-6 valve spring problems, old saybrook ct, saab 900

Question
My wifes precious Saab started running very rough this morning- so she wisely pulled over and called a tow truck. Our mechanic said that two of the valve springs appear to have sacked out, and now informs me that one valve stem appears to be bent. This same mechanic also just changed the seals on the cams, the valve covers and the front of the crank 300 miles ago. He swears the timing is still spot on, and I do trust him. Any ideas on why 2 springs would go south under low speed driving? What else should I be looking for to avoid more of this in 500 more miles?

Answer
Steve:
 While its quite rare for valve springs to fail, they sometimes do...simply from age & fatigue. The fact that two seemed to have failed is even more baffling...although it does suggest a "bad batch" possibility. It is also difficult for me to explain a bent valve stem from 'above' (you did not say that the head was removed)although I suppose a fatigued or broken lifter could have put lateral pressure on it.
What I would suggest, due to multiple inexplicable unknowns, and the fact that the SAAB is PRECIOUS, is to get a completely rebuilt head, not using any components from your present one. There used to be a place that specialized in rebuilt SAAB components, including heads, in Old Saybrook, CT. (Ericcson Industries), but I don't know if they are still active. Costly, but 'precious' things are...............

         Hope this helps