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Upgraded mercruiser 4.3 prop

Hi. I recently upgraded my 1996 mercruiser vortec 4.3. My current prop is a 13 3/4 x 21 vengeance. The upgrades added 100 hp over the stock 190 hp and I'm figuring a 24" pitch is what I will need. The alpha outdrive has a 1.81:1 gear ratio and the boat is only used with a light load. The boat is a Donzi runabout and weighs 3000 lbs plus one or two people and fuel. The engine is still in breakin period with only 8 hours usage on the 20 hour breakin period. For the first 10 hours, I am keeping the rpm between 1500 and 3600. For the next 10 hours of usage I will go above 3600 rpm for short periods.
I'm looking for a performance prop for top speed, because the boat is always lightly loaded. Props I am considering is a laser, tempest or fury. Does anyone have a fury on a sterndrive? Like above, I figure 24" pitch with a diameter not too small or too big. I can't get any rpm/speed numbers yet, because I'm not operating the engine at WOT. With the current prop I figured I will have 5,500 rpm at WOT. I feel I don't want to operate the engine 700 rpm over recommended WOT of 4800. I'm thinking of purchasing a cheap prop with a 23 or 24 pitch and see what numbers I have after the 20 hour breakin period. Any prop suggestions if my initial numbers are correct?
 
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