CV 746 C PCV valve differences

[Salvatore]

I saw a survivior 1969 Z/28 at MCACN a few years ago with the heavier, spun steel PCV valve. Steve Shauger and Johnny K. might remember that car too. I also believe that the purple valves were 1970 and up over the counter. I personally never saw a purple PCV valve on an assembly line car but its tough remembering back that far for sure. I worked at a Sunoco and also a Hess gas station from around 67-68 to about 1971.I have seen survivor, one owner sb cars 307, 350 etc. with the heavier spun PCV valve but not sure if they were just in the early 69 model year or not. Also saw some 350 2 barrel 69 chevelles in the yards with the spun steel valves. Maybe John Karvonen and Dave Valentin can chime in here.