What I mentioned about the pump being more efficient applies regardless of a raised rev limit. I mention the rev limit thing because that makes it even more important. I'm sure someone will chime in here, but by spinning the pump a bit slower, it SHOULD become more efficient because the pump isn't spinning furiously. I'm trying to think of a good analogy for you
OK--here's one, although maybe not pertinent, because it's kinda the tail wagging the dog. Think of the old merry-go-rounds on the playground. Assume you're the one standing to the side spinning it. It's always easier to spin it hard if it's moving slower. If the thing is moving really fast, it's harder to get your hand in there, moving faster than the ride, to speed it up further. Again, the tail wagging the dog, but the best analogy I could think up.
An example: The SR20DET. Notorious for overheating. The fix: slow the pump with an underdrive pulley, and a lower-temp thermostat. Don't flame-I know the SR20DET's waterpump was poorly engineered. But the example still applies. If you spin a pump faster than it was designed to go, it won't work as well. Slow it down in relation to everything else, it works as intended...
Now, John(Orange) may be right about the longevity of our particular application. I dunno. His situation is unique(329 whp), so I don't know...
Greg