New water pump 6 impellers whats up with that!

In 40 years of working on engines, I have never seen cavitation effects on a water pump impeller. It is unlikely that you can spin one fast enough on the average engine to cause cavitation.

The factory did speed the fan drive up a little in A/C cars. Not a lot compared to some other manufacturers, but some.

The redesigned pump housing will have a lot more to do with the flow capacity of the pump than the blade count. Reducing the impeller to housing clearance of this type of pump has a dramatic effect on performance. Modern manufacturing methods make it very easy to produce more precise parts.

Post picture of the changes that you can see in the newer part, and the older part you think is better.

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