. . .So looks like PCV (or PVV as Bill and TC's info indicates) was possibly an option way back, at least in 61/62 it was RPO242.
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Anybody have a twist on vent cap part number, that fits a 235 cover? can only find clip on type.
What is PVV?
GM called it PCV in Advance-Design trucks.
What do you mean by a twist on vent cap?
The oil filler cap on the 216/235/261 valve cover?
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vented filler cap -
unvented filler cap 
