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Trim and Prop Size

MagicMan

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I have 28 magic with 496HO bravo 24P prop, been playing with the trim a bit and noticed that I can never fully trim the drive. When I do trim the drive above the1/4 mark I lose power. I don't have the boat loaded, usually just me and the wife. Max mph on the gauge is 55-57 mph. The rev limiter beeps at WOT with the trim down. What am I doing wrong. I usually cruise the boat at about 40-45 mph 4500 RPM with trim below the quarter mark any higher its starts powering down. Do I have the wrong prop? Read through a couple of prop threads here and found most people have same prop with engine configuration and are cruising at 60 mph or higher trimmed up.
 

02HoWaRd26

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Try asking again in a few weeks, boats have no place here this week.
 
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EBT531

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Thats a pretty big boat to "cruise" at 60mph even trimmed up with that motor. I would think its a low to mid 60's boat top end. What RPM are you hitting at WOT that the limiter is kicking in? The air sucks right now, but if you are hitting the limiter then usually you can handle more pitch. I
 
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MagicMan

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Thats a pretty big boat to "cruise" at 60mph even trimmed up with that motor. I would think its a low to mid 60's boat top end. What RPM are you hitting at WOT that the limiter is kicking in? The air sucks right now, but if you are hitting the limiter then usually you can handle more pitch. I
Im hitting 5000-5100 RPM WOT boat trimmed at about 1/4 55-57mph
 

EBT531

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Im hitting 5000-5100 RPM WOT boat trimmed at about 1/4 55-57mph

See if you can borrow someones 26, if you don't lose too much time getting on plane you should be good as you'll only lose 200 rpm's or so. I've got a 29' with a 500efi and run a 26 most of the time. I have a little more power but also more weight so it probably evens it out. Another factor could be if you bought your prop new and its truly a 24. I've heard stories of even factory props can be off a pitch or so.
 

98special

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26p sounds about right to me. I bought my ULTRA used and just had bellows and gimble bearing replace, trim was WAY off.
Might want to measure you trim cylinders at full extension. Max extension I think is 21 3/4" center of bolt to center of bolt (Bravo1). Then look to see what your trim gauge reads. Adjust trim sender as needed. Some boats like a little more or a little less trim.
 

BDMar

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How do you know you're not getting full trim? Does it have a trim limit switch and is it adjusted correctly? Also, on that boat if it starts losing power when you keep trimming it up you have gone past the point of the propeller holding water and it's basically trimmed too high. General rule of thumb is trim it until it starts to slow down and rpm's raise, then trim back down a little. Proper trim is when you get the most speed for the rpm's. If you're hitting the rev limiter at proper trim level you need a higher pitch propeller. I would think a Magic deck with a 496 at best is a low 60's boat. Definitely not a cruise speed.
 

MagicMan

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How do you know you're not getting full trim? Does it have a trim limit switch and is it adjusted correctly? Also, on that boat if it starts losing power when you keep trimming it up you have gone past the point of the propeller holding water and it's basically trimmed too high. General rule of thumb is trim it until it starts to slow down and rpm's raise, then trim back down a little. Proper trim is when you get the most speed for the rpm's. If you're hitting the rev limiter at proper trim level you need a higher pitch propeller. I would think a Magic deck with a 496 at best is a low 60's boat. Definitely not a cruise speed.
Thanks for the input.
 

Wmc

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Had same boat, power and prop. 69mph at best. Usually 65 all day long. Cruise 50-55. Never hitting rev limiter. Maybe you prop had been worked on.
 
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