On a side note - I had closed cell foam (but with a foil face) installed on the hood of my 2002.
Had that for almost 30 years - I appreciated that the foil acted as a heat reflector - but more importantly, did not allow the foam to absorb anything the engine threw up at it. The shop in Monterey that rebuilt my engine installed that (I don't know where they sourced it - and as that was in 1986 or so, who knows if that would even be available).
I know it was not stock - but, worked great (even though it did not look 'perfect' after being there for those years. See pic taken when I sold the car.
I inquired with sfdon about this kind of foam when he had my E9 - but could not find anything better than the OE style that he ended up installing.
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