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Prop help for a 38 zr

Old 06-01-2011, 08:27 AM
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Default Prop help for a 38 zr

I have a 38 zr with staggered 525's currently running 34 pitch 5 blade labbed props. Was out this weekend and was hitting the rev limits at about 80 mph. I know the boat has more than that. Any suggestions?
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Old 06-01-2011, 09:38 AM
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Are you sure they are 34 pitch 5 blades?

I have 34 pitch 5 blades on twin 700hp motors and pulling 115mph on my 38 ZRC.
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Old 06-02-2011, 12:16 PM
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They are 100% 34 pitch 5 blades.
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Old 06-02-2011, 07:23 PM
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ZR's with 525's usually run 30-31 pitch 5 blades, are they herings?
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Old 06-02-2011, 10:19 PM
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something dont sound right
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Old 06-03-2011, 09:00 AM
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They are not herings. My mechanic tells me i haven't found the boats sweet spot yet. I think he's just full of sh*t.
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Old 06-03-2011, 10:03 AM
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what rpm are you bumping the limiters? with 34s you should not be close to that... how are you trimming the boat? is this boat new to you?
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Old 06-03-2011, 10:35 AM
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It sounds to me like you are way over propped and are over trimming it to get the RPM up. The trim on a ZR should be at 2 to 3 max. anything over and you are over trimming it. I would bet dollars to donuts those are the wrong props for the boat.
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Old 06-03-2011, 04:43 PM
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Maybe he's running 1.65 gears.
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Old 06-04-2011, 02:48 PM
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Originally Posted by Marginmn
Maybe he's running 1.65 gears.
I assume 525's came with XR drives, and they don't come in 1.65's that I know of. I think the lowest and standard is 1.5

My opinion is to do the math (i.e., get your ratio and figure out where you think you should be) then try some props.

Like Tom said the step bottom boats don't like trim like flat bottom boats do. I was on my limiters because my props were too small but now I'm doing well with bigger wheels but still pretty well neutral on the trim.

With big cruising wheels I can get to nearly the same speed by trimming out. So the prior owner might have put bigger ones on to max out cruising speed.
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