30ft Cobalt Arneson Blown BBCs prop suggestions

Discussion in 'Props' started by Tartilla, Jun 29, 2023.

  1. Tartilla
    Joined: Jun 2023
    Posts: 2
    Likes: 0, Points: 1
    Location: BC

    Tartilla New Member

    I just got a 30ft Cobalt Condurre 300.

    Has ASD6 Arnesons, powered by 650hp Blown 454s.

    Sat for many years, and doing a refit now.
    Engines and drives have about 25hrs.

    Max RPM is around 5200, but orig owner never put the throttles to the boards.

    The story is, the hull ended up being squirrely at speed...so he never pushed it past 4500rpm. Not sure exact speed.

    Need to figure out the hull...and trim it out to solve that a little at least.

    Hull is 26° deadrise.
    280 kplanes parallel at outside ends.

    Arneson reduction: 1.32
    Trannys are 1:1

    Current props are:
    Rolla 17" x 25 5 blade cleaver
    Heavy cup

    What expected dynamic pitch will I get with these?

    What is the optimum slip for surface drives?

    If I have the power...is getting larger props better?

    Also need to find spares. Have 19 spline...but will get the 26 Spline adaptor.

    Is the rake info on my prop?...ref photo



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