I don't understand various things about why Porsche doesn't compete in F1.

Yes, F1 is expensive but I think sponsors will be lining up to put their logos on a Porsche F1 car.

Next, F1 is where so much of the cutting edge technology is developed. It would provide Porsche with an even better arena in which to do this.

If it's a question of cost, why then has Porsche sunk so much money in the past into racing in Le Mans? They've won it 16 times (I think).

Ferrari make sports cars to fund its racing team. Why doesn't Porsche divert some of its loot into racing rather than buying 20% of VW????

Surely, the appeal and image of Porsche will rise yet higher if they win F1 races. More buyers, more cash.