Looking to build a hood scoop plug and needing advice on which type foam to use. I know some just don't last. This scoop came from Eastex race cars and I can't find a plug close enough so I thought I would make one.

Find a fabric store, around here we have Joann fabric, they normally have like a "scrap" section. Not sure what type foam you need but yea some foam just crumbles and some will actually stay together.

I have always got mine from a fabric or upholstery shop. Closed cell foam is what they are generally made from.