No. I mean they are so restrictive they don’t let the pan evac function. There should be check valves on the stand pipe in the collector. That should keep any backpressure getting to the crank case.
IIRC, there were some of those baffles that had steel reeds in them and some had fiber reeds. They both wear out and need to be checked because they will both eventually fail. The fiber reeds fail much quicker because they can’t take the heat.
In fact, I forgot who told me about the reeds but I remember he said the fiber reeds sealed better than the steel ones but wore out much quicker.
I know guys who’ve run the same baffles for years and years and never checked them. The best I did was two seasons on alcohol.
