(didn't re-read the entire thread again)...but didn't at some point one of the rockers break idling through a parking lot or something?
if so...I suspect there are other issues...the 'time to close' at idle/near idle rpm is soooo long that stiffer springs are probably not going to fix it..
worth a shot, I guess...as the other alternative is pulling the head(s) and measuring valve recession and piston protrusion.
Yes, actually all times rockers have broken have been at idle. First was in a drive thru, second was idling while fueling, third was sitting in the parking lot gathering the courage to walk his happy ass back into work that day, or as he called it, letting the truck cool down a little before shutting it off. I never have gotten a straight answer as to how hard he was driving before he was idling, but, youd think that contact damage would break them under hi rpm/boost/back pressure situations.
And my dumb ass forgot to get pictures today... :doh: