"Firs of all I've heard that Audi spends as much into their LeMans Program."

NO! Audi may have spend over $150 million on the R8, but they did not spend $300 million a year. The money spent on development of an F1 car could be spent much more efficiently developing a better road car (and GT racer). It would be great to see Porsche in F1, but should they do it? An F1 program would only make sense for Porsche if it were paid for in large part by a sponser or current F1 team. Remember the current top F1 teams must pay for a large portion of their budget. Also, Porsche turned down Sauber when they offered to pay for a Porsche F1 engine program in the late 90's. Why would they return to F1 now? Porsche CEO would never approve an F1 budget. Porsche is not BMW or Toyota.