Thanks for the informative replies gentlemen. It was something that crossed my mind after reading a Sport Aviation article that said quote "PS foam has little to do with the strength of the finished process. It is merely a filler and, most important, a built-in mold or form"
Having read some of the replies, I will certainly be leaving the foam in place and look at other areas where I can reduce the weight. Installing a Jabiru 2200 works in 2 ways. The 135lb installed weight is one, and lightening my wallet of $13,750 AUD is another. Thanks again. Rob. Robin Wills Second Person, Pacific National KR-2 19-4594, Ser# N111 krvia...@bigpond.com