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  1. #1
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    Z7 Need More Trim

    I bought a 2015 Z7 end of last year with a 175 XS pro 24 pitch Tempest plus, large PVC plugs. Added a 8" jack plate, motor 3" under pad, when at WOT 5,500 RPM not getting enough bow lift I think. With a decent load, 2 people and 3/4 tank of gas I can only get 61ish. I know there's a few more MPH I should be getting with this setup. When trimmed all the way up i'm not feeling the bow lift i had in my other boat.

    I know the prop can be custom worked to give me more lift. Is there anything else i can try?

    I based this setup on my prior 2007 591 with a 150 opti-may 6" jack plate 24 pitch tempest plus motor 3" under pad and i could get 61MPH at 5,200 RPM fully trimmed up. Sometimes in the right conditions when at full trim this setup start chine-walking so i know i was at my lift limit.

  2. Moderator Fishysam's Avatar
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    #2
    How did it run before the jack plate addition? What is the overall condition of the prop?
    Mercury 250 proxs 2B115089

  3. Dogfish_Jones
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    #3
    You might be getting just about all she's got at 61. Now that's saying are you are running on smooth as glass water and no wind, or somewhat choppy water?
    An example, I have a 2015 Z7 but with a Mercury Pro 150 and with two people on smooth water with what you listed I get around 57…58 mph via GPS. By myself, I might reach 61 even 62 depending on gas and load. I do not have a jack plate either. Going to get one, an 8" JPL.
    I would think you would get better than 57 mph than me because you have the 175 but not that much better speed, no more than 5 mph I would think. This would put you up in the 61 or 62 mph speed.

    We have the same prop also for reference. My tackle load is pretty heavy too, both rear compartment full and the front center section full of tackle boxes. I have an addiction to buying way more tackle than needed.

  4. Member
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    #4
    Try a known good prop if you can

  5. Member
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    #5
    I run a 2014 Z7 with a 175XS and a 24 Tempest. I also have a 6" Atlas and twin 10' power poles. Depending on the load and weather conditions, I will run anywhere from 2 1/2" to 3 1/2" PTP. You are right - there should be more speed, albeit limited, but you just have to find where it is. I would play with the prop to pad first because it is easy and free. Also, your current setup should be juxtaposed to your old boat - not the same. They carry their respective loads differently; they have different weights, and they have different motors which means distinct resistance variables.

    To figure out my setups, I ran the boat without a lick of tackle, limited fuel and just me. Then I ran it loaded down with a full tank of gas. Obviously, there was a marked difference where my jack plate was set. Now that I know my range it is easy to adjust on the fly.

  6. Moderator Fishysam's Avatar
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    #6
    To me not getting any bow lift kinda sound like motor is to high for that specific prop
    Mercury 250 proxs 2B115089

  7. Member
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    #7
    The prop is in excellent condition. Outboard has just over 10hrs. I never drive it without a jack plate prior to purchasing last December.

    Quote Originally Posted by Fishysam View Post
    How did it run before the jack plate addition? What is the overall condition of the prop?

  8. Member
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    #8
    I will try lower the jack plate and see if anything changes. When trimmed all the way up at WOT i'm not throwing much of a rooster tail. If i could trim a little more i'd think it would give me more bow lift and a few MPH faster. I know they make alum wedges to achieve more trim but thought there was something easier to try.


    Quote Originally Posted by remaly181 View Post
    I run a 2014 Z7 with a 175XS and a 24 Tempest. I also have a 6" Atlas and twin 10' power poles. Depending on the load and weather conditions, I will run anywhere from 2 1/2" to 3 1/2" PTP. You are right - there should be more speed, albeit limited, but you just have to find where it is. I would play with the prop to pad first because it is easy and free. Also, your current setup should be juxtaposed to your old boat - not the same. They carry their respective loads differently; they have different weights, and they have different motors which means distinct resistance variables.

    To figure out my setups, I ran the boat without a lick of tackle, limited fuel and just me. Then I ran it loaded down with a full tank of gas. Obviously, there was a marked difference where my jack plate was set. Now that I know my range it is easy to adjust on the fly.
    Last edited by Scully; 11-14-2017 at 12:52 PM.

  9. Member
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    #9
    Sounds like you need to come up with the motor.

    Raise the motor until you start loosing water pressure or start loosing speed. Then drop down until water pressure comes back and or speed. The tempest prop likes to run higher than other props.

    Although I have a different boat NX-882 (I believe older brother nitro, 18+ foot) with 150xr6 I am running 2-1/2 inch P2P with 8inch setback )nonadjustable) 23pitch tempest plus +15psi water pressure. My self with the current temp in the 50's elevation here is around 1200feet. 63gps at 5650r's. Two people livewell full half tank 59 @ 5500r's.

    When I got the boat, the engine was at 3-1/2 inch roughly. would only run 56 to 57 not sure on rpms. Just by raising 1/2 inch was a HUGE improvement. Holeshot, speed, rmps came up. Kept going up until where I am at now.

    By raising the motor it will actually give you more lift with that prop.

  10. Moderator Fishysam's Avatar
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    #10
    If not throwing rooster I'd go up, not down like I originally said. Ad since the motor has only 10 hours on it I would straight up can it for 20 minutes straight. No lifting the throttle
    Mercury 250 proxs 2B115089

  11. Member
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    #11
    rooster tail should be no higher than the height of the motor. Otherwise it's just wasted energy.
    2015 Nitro Z-7 175 Pro XS

  12. Member
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    #12
    Thanks for all the advise. Will raise motor in the spring and see what happens.