Big Motor Big Prop Mounting Height Jackplate

Capman

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We enjoy it. Don’t go WOT all that often. Prefer to cruise around 25-35
I agree completely. A majority of our time will be spent cruising and pulling wakeboarders and kneeboarders. Thanks for the information.
 

Paradise bound

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I have been having the changing prop bug also ,when I bought the 23 RSB /350 Verado they had it sitting in the top hole (Motor Up) I had them immediately lower before I even took delivery ,from reading on this board it was way too high. so didn't even test ,originally came with a Enertia 19P was getting 52 and felt it still had some room to grow . I spoke Bennington unfortunately they couldn't help so then spoke with a "prop guy" about what direction to go because everyone was running the Enertia 17 ,he recommended the Enertia Eco ,so I bit the bullet and purchased one ,I've run it for quite sometime and can say ,it definitely gets you up out of hole quick but I've lost 2mph on the top end , I came across a smoking deal on a 17P Enertia ,its sitting in the box waiting for it's testing day
 

Capman

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Good to know. Anxious to hear how your testing goes. Good luck and let me know if you don’t mind. Thanks!
 

cwag911

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52 MPH at what RPMs?
 

Keith P

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I have been having the changing prop bug also ,when I bought the 23 RSB /350 Verado they had it sitting in the top hole (Motor Up) I had them immediately lower before I even took delivery ,from reading on this board it was way too high. so didn't even test ,originally came with a Enertia 19P was getting 52 and felt it still had some room to grow . I spoke Bennington unfortunately they couldn't help so then spoke with a "prop guy" about what direction to go because everyone was running the Enertia 17 ,he recommended the Enertia Eco ,so I bit the bullet and purchased one ,I've run it for quite sometime and can say ,it definitely gets you up out of hole quick but I've lost 2mph on the top end , I came across a smoking deal on a 17P Enertia ,its sitting in the box waiting for it's testing day
The 17 pitch prop should get your RPM higher and still be w/I the recommended operating range. I believe that will improve both performance and fuel economy. 5900 RPM is at the low end.
 

RodEarl74

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I've never been able to get my 350 Verado over about 6000 RPM's at WOT. When I have it trimmed to maximize speed and RPM, max I can get is 50.6MPH at 6000 RPM.

When I try and trim just a little more to maximize RPM at the 6400 Mercury claims, my Prop starts to lose bite... Not sure if this is normal or not. Running the Enertia 14x17p prop that came on the boat
 

JDB

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I have a few minor updates to add to this ongoing educational process which is far from complete.

If you have a Big Yamaha stick with the SWS Props and if you have a Big Mercury the Enertia is the best choice.

The Yamaha SDS is the softest on the gear engagement and I believe the early ones that used a separate plate are the best in terms of smoothness.

As the props get smaller in diameter they seem to want to be deeper in the water to drive these Semi-Planing Hulls.

The last two props I tested were the 15 1/4 X 19P and the 15 X 20P and they are both "asking" to be run deeper as only the slightest (approx 20%) trim angle can be tolerated without a counter productive level of ventilation.

My current belief is that the Highest Mounting Height available to us on these 25" ESP's or equivalent, which I am currently running is too High for the higher pitched / smaller diameter props so I am planning to lower the Motor down a hole and continue testing.
Also I can't see much potential benefit from adding a Jackplate!

Keep in mind that our surface water temps are at 90 Plus degrees currently.

Spray Management, Low Friction running surfaces on the tubes and getting the boat out of the water looks to be the REAL way forward on speed and efficiency.
 

Potomacbassin’

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Putting an AED to the thread.

Have a 23SSBXP with SPS+ and F250xca. I specified in the contract that the boat come with a SWS2 prop, but of course the dealer disregards and puts what they think the boat should have. Running a Reliance 14.25 x 17.

Initial impressions are terrible. Boat in the low and mid range is fairly flaccid and only above 4000 rpm does it start picking up speed. By 6200 rpm with half tank and two people boat speedo is 47. There is still another inch of play in the throttle before hitting the stop, so my conclusion is that I’m way under-propped.

I suspect the diameter is the culprit for the low rpm woes, that 250 per the Yam prop selector should be 15-15.5. 17p appears to be in range but again the prop selector shows the motor can handle a few more inches. Also the Reliance series is not recommended by Yam so I will demand my SWS2!

Lastly motor is in the lowest position so I will have the dealer move up a couple of holes when the motor gets it’s 20hr service. I don’t do any water sports so cavitation will only be a problem (I assume) when running through larger waves/wake.

Will post any findings.

thanks
 
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