[krystalandashley]

I recently imported a Mariah Z238 cuddy from Cinci to Australia. Our family primarily does watersports ie skiing, tubing etc. The prop on the boat was a Mercury Revoultion 4, stainless steel 4 blade, 21 pitch. The motor would only rev to 3700rpm max, and was slow out of the water. I contacted a prop specialist here and told him how we do watersports 2 adults + 2 small kids, our motos size 5.7 L EFI, and he suggested we try a 14 1/8 x 18p. This improved the pull out of thewater but only would rev up to 4100rpm, but in saying that was an improvement on the original prop from the states. The prop guy here now has suggested a 14 1/2x15p which he says should now rev up to 5000rpm.
Does any one have any feedback or suggestions on the what they think is the right size prop for the watersports and rev range required.
Thanks

[mikeyt]

The Revolution 4; 14.625 x 17" pitch should work just fine on your boat at least according to the Mercury prop selector tool. The recommended rpm range for the 5.7 EFI is 4400-4800 so following the advice of your prop "expert" in Oz will put you over that range which will cause excessive fuel consumption and extra wear & tear on the engine/outdrive. A 14.5 x 17" Vensura might be another good option as it is designed for watersports. The Rev4 is more of an all-round prop. Both are 4 blade props which tend to be better for watersports anyway.