That is true, except for a few things. First, the foam was originally wrapped with duct tape to hold it in place. Second, the impressions made by the underhood bracing showed that the foam wasnt moving . Those impressions are long gone, because these have been sitting on a shelf for at least a decade. Third, if the seal was no good, why did it have an effect, demonstrably slowing the car down in A to B tests?
