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fs5
09-30-2012, 10:33 PM
i have a slt boat(inflatable tunnel hull) its a gemini zx3 same as a mako xtm, i run it with a 55 merc seapro.the hijackers have a slight rocker on them right at rear.i've had the boat for over 4 years now.i have a problem with the boat purpoising when using cleavers.
i've ran a few choppers on it including one of ron's and both the old merc chopper and various chopper II on it .they all ran fine ,but were getting around 15/19% slip.
i've ran a few old rubber hub merc cleavers on it that were 11 x 18p 20p 22p .i could never get the boat to settle though,it would purpoise pretty bad .
i've tried a couple of the newer merc 12 x 20p 22p cleaver props and they ran great.i wish i had the dollars to buy a new one.
i now have a 15p trophy sport 4 blade thats been cupped and 1 inch of pitch added ,the boat runs like its on rails.but its not enough pitch..
dose any one know what rake the merc choppers are also what rake the new merc cleavers are and the trophy sport?
dose more rake give you more bow lift?
thanks

mark sholund
10-07-2012, 11:58 AM
Fs5,

More rake more bow lift.

Try adding more center of blade pitch. This will work very well on your set up.

Keep Testing one thing at a time,

Mark