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Drive spacer or not?

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Old 09-22-2022 | 02:19 PM
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Have done some testing

Hydro p5x 24", good bow lift, feels smooth, planes nicely, still very little ability to trim at lower speeds, porpoising only at full throttle.

3000rpm, 35mph, 23% slip
3500rpm, 42mph, 21% slip
4500rpm, 60mph, 12% slip
4800rpm, 64mph, 12% slip

Bravo 24", good bow lift at lower speeds, planes nicely, feels loose, can feel some vibration at docking speeds, almost zero ability to trim at any speed. Scary at full throttle, at 5000rpm it looses bite complitely, maybe too much stern lift, dont know.

3000rpm, 32mph, 27% slip
3500rpm, 42mph, 18% slip
4000rpm, 48mph, 18% slip
5000rpm, 60mph, 18% slip

Next test with powertech ofx 24" 4blade.
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Old 09-22-2022 | 03:59 PM
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Originally Posted by JaniH
Have done some testing

Hydro p5x 24", good bow lift, feels smooth, planes nicely, still very little ability to trim at lower speeds, porpoising only at full throttle.

3000rpm, 35mph, 23% slip
3500rpm, 42mph, 21% slip
4500rpm, 60mph, 12% slip
4800rpm, 64mph, 12% slip

Bravo 24", good bow lift at lower speeds, planes nicely, feels loose, can feel some vibration at docking speeds, almost zero ability to trim at any speed. Scary at full throttle, at 5000rpm it looses bite complitely, maybe too much stern lift, dont know.

3000rpm, 32mph, 27% slip
3500rpm, 42mph, 18% slip
4000rpm, 48mph, 18% slip
5000rpm, 60mph, 18% slip

Next test with powertech ofx 24" 4blade.

No offense meant at all... but you're a bit ignorant with your shared methodology. You may find benefit to including someone who is well versed in regard to setting up a boat similar to yours. Again, please don't take this the wrong way.... I am more than ignorant in many areas.... finding someone who isn't is always a good idea. *Generally, if you don't need trim and the boat is running bow proud at zero or negative trim, you need a spacer. Not sure about your application.
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Old 09-22-2022 | 11:54 PM
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Originally Posted by Joe
No offense meant at all... but you're a bit ignorant with your shared methodology. You may find benefit to including someone who is well versed in regard to setting up a boat similar to yours. Again, please don't take this the wrong way.... I am more than ignorant in many areas.... finding someone who isn't is always a good idea. *Generally, if you don't need trim and the boat is running bow proud at zero or negative trim, you need a spacer. Not sure about your application.
Yes I am an ignorant, and that is the reason for me to be here asking for help, and learn something. Hope i can share my knowledge in future. If i get any. 1" spacer is ordered and on its way. Thanks!
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Old 09-23-2022 | 05:28 AM
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https://linksharing.samsungcloud.com/7P9Sj9YMleGG
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Old 09-23-2022 | 05:43 AM
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https://i.imgur.com/y4Q7mbE.mp4

here is a video at WOT, p5x, 64mph

Last edited by JaniH; 09-23-2022 at 06:03 AM.
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Old 09-23-2022 | 05:21 PM
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Does the boat have trim tabs?? If so, what kind and are they raising enough??
Have you checked the bottom for hook in the last 4-6 feet?? Hook will do the same thing as dragging tabs.
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Old 09-23-2022 | 11:51 PM
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Originally Posted by Griff
Does the boat have trim tabs?? If so, what kind and are they raising enough??
Have you checked the bottom for hook in the last 4-6 feet?? Hook will do the same thing as dragging tabs.
The bottom is blueprinted complitely, there was a sligth hook but not anymore. No trim tabs.
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Old 09-25-2022 | 08:36 AM
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Your inbox is full
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Old 09-25-2022 | 11:12 AM
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Originally Posted by Alexanderlindahl
Your inbox is full
not anymore 🥳
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Old 09-27-2022 | 03:12 PM
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Originally Posted by Alexanderlindahl
Your inbox is full
Any gains after labbing the p5x?, it is smooth running prop for sure!
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