Question for the guys with water cooled Porsches. Ever used a water pump with a metal impeller ? OE has a plastic impeller. Most aftermarket pumps are metal. Internet Chickenlittles say that will destroy your block if the pump goes out. My '08 3.4 puked its pump today and it seems absurd to pay $300 for a pump with a plastic impeller when the metal ones are $75. Soooo has anyone seen a metal impeller chew a hole in the block ??
