The aluminum impellers are NOT limited by rpm, but rather HPabsorbed. You don't have enough information in any posts to tell you what needs to be done other than to kick your buddies out of the boat.
Jet boats live and die from weight and weight distribution.
Anything past around 500 HP and I say lose the aluminum impeller.
A shoe and a rideplate may or may not help, but at the same time, if done right, won't hurt either.
You should have enough HP to make the droop work for you, as long as you can fly the bow I say run it.
JMHO
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