[RWebb]

any fan is "expensive" in terms of a parasitic load on the engine

here is another tidbit:

On the 1963 911, the cooling fan took only 4.7% of the 901's gross engine output - Ludvigson, EXCELLENCE WAS EXPECTED, 1st ed., Ch. 16, p. 402

I should have some data on fan vs. water pump for VW motors somewhere - will post if I get a chance to search for it...