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Hey Phil,

Got the boat back today. Despite multiple conversations, and diagrams and print outs from Whaler Central with highlighted sections on mounting height, they mounted the motor... one hole up.

Here is the real world testing data I got back from the rigger with the new Mercury FourStroke 90 with 2.38 Command Thrust gearbox and aluminum props:

14.25" x 21P 5600 rpm 44 mph
(unknown diameter) x 17P 6150 rpm 32 mph

With data entered for acceleration, 21P, 5600rpm, and 44mph, the Mercury Prop Selector gives the calculated pitch at 19.60, rpm at 6000, and speed at 46.79mph. It recommends an Enertia Eco 19P, or the regular Enertia in 20P or 21P. However, the Mercury Prop Selector doesn't seem to include the Enertia Eco 20P in its programming, because the recommendation skips directly from 19P to 21P depending on how you tweak the inputs. In fact, I don't think it includes any even numbered pitches for the Eco.

Based on the calculated pitch of 19.60, I've got a line on a used Enertia Eco 20P, but I'm worried that maybe a 19P would be better? I was also hoping the 20P could work if I played around with the performance venting to help it spin up a bit faster.

Thoughts? Thanks for your advice.