[Putershark]

If you look in the engine section I posted a thread that had a link to all the performance data for Triumph boats that I could find on the Internet Engine performance guides
Just compare makes and models for any 2 stroke engine that is close to yours as a starting point.

This thread here may also help Online Boat Prop Calculator

You can also mount up a Pro Pluse prop and change the pitch till you get a rough idea of which Stainless model to use and then save it as a good back up prop that will not rust or add a lot of weight to the boat.

Some Mercury dealers have a Prop trial program that you can buy and switch till you find one that works for your boat. Their web page in the prop section I think has a dealer locator that will show you which one offers that service

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