What about a system that uses the best of both approaches? It sounds to me the downdraft tube might be preferable at speeds over 30 mph or so. It sounds to me the PCV system might be preferable at idle and at speeds up to 30 or so. The crankcase needs a slightly negative pressure to help discourage oil leaks as well as to evacuate blow-by. Surely we have enough brain power to solve both challenges here, yes?
Jon
