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Gps speedometer

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Joachim

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New Bennington owner 2250GSR with a 200 HP 2.8L in line 4 cylinder.   Does anyone have any advice on a good iPhone GPS app.


i have the GPS speedometer option on my helm gauges but i swear it is not reading correctly.  Example 5000 RPM and it reads just 30 mph.


20 gallons of gas and 4 adult passengers.  Prop is a Reliance SDS 14 -1/4 x 17.   Has17 hours on the boat
 
Is that WOT? Is 5000 rpm full throttle? WOT should be 6000.
 
I had asked and started a thread about speed apps back around May 4 I think. You should be able to search for the thread and responses. Lots of suggestions but for free you can try them all. Search the App Store for free GPS. I haven't found a favorite yet but seem to open the one called simply "speedometer" most (maybe because it is the first one listed on my phone)
 
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I like Speed Box. It's a free app and performs the most basic functions. I use it in an iPhone.


PS, I think you need a 15 pitch prop.
 
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Joachim, what hull configuration do you have -- tritoon with ESP? SPS? I have your same motor and prop size (although not SDS) and with clean toons I'm at 5800 rpm and 44+ mph with my SPS hull.  Lakeliving also has the same motor with a 15 pitch prop and also gets a similar speed, and although your boat "may" be heavier than ours (G is heavier than an S but we're 2 feet longer), it seems something is definitely off with your RPM and top speed.   
 
I am running with the ESP toon pkg.


seem to be only able to get up to 5000 rpm at full throttle .  


Anyone have any input why I am not running at full rpm capacity?
 
Too much pitch on your prop. If you want to increase RPMs at WOT, reduce the pitch.


As I said, I think you will get more revs and speed with a 15 pitch prop. First, ask your dealer what the logic was with delivering the boat with a 17 pitch prop. Ask them to loan you a lower pitch prop to try out. My dealer agreed to this provided I paid for a second prop and brought back either the original or replacement undamaged. I brought back the original as I got more speed and lower RPMs going from a 13 to a 15 prop with it. So as you can see, every boat responds differently.


If your dealer isn't helpful, check with a local prop repair shop. They often sell used props and may have one or more for you to try.


It's always best to keep all the variables constant, so try to do your testing on the same day, at the same temps, in the same lake conditions with the same fuel and passenger load. And top position. Once you have these all these constant, the only differering variable should be the prop.


My money is still on the 15 pitch.
 
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Thanks for the input on the app and discussion on the prop .  I will see what the dealer will do for me.
 
I have the 2275 GL with same motor and I can hit 42  WOT consistently. I have hit 43 sporadically.  With four adults and two teen agers and equipment, still able to hit 38-40 WOT.  Your boat has more weight than mine as you have ESP. Goldnod is right you need 15 pitch. You should be in the 40 range with that set-up.
 
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Joachim said:
Thanks for the input on the app and discussion on the prop .  I will see what the dealer will do for me.
Click to expand...

Be prepared for the dealer to push back and defend their prop choice. Mine did, but I insisted.


To this day, I think they believe I am making up a story about getting more speed at lower RPMs. (I know this is the opposite of your problem, but the solution is the same).


Prop science is a complicated science. Some of us paid more attention in science class than others...... ;-)
 
PS: I am moving this topic to the "Members Zone: Props and Power" forum where it is better suited.
 
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Update and correction.


i downloaded speed box app used it today and the speed was exact to the GPS speedometer on the boat. So that was great.


turns out I was mistaken on the prop size.  It's actually a SDS Reliance 14 1/2 x 15.


i ran the boat today with only myself on it and was able to get 5600 RPM and 40 MPH after I trimmed up the motor to approximately the 1/2 mark on the gauge.  Without trimming the motor I can't get above 5000 RPM's.


i'm not real experienced with a high HP pontoon as I just traded up from an old aqua patio with a 50 HP.


do you guys usually trim up the motor to gain max speed?


what is a safe amount to trim up without causing issues?
 
Trim it up till you lose speed or slip. I don't look at the gauge, I do it by feel.
 
Joachim said:
Update and correction.


i downloaded speed box app used it today and the speed was exact to the GPS speedometer on the boat. So that was great.


turns out I was mistaken on the prop size.  It's actually a SDS Reliance 14 1/2 x 15.


i ran the boat today with only myself on it and was able to get 5600 RPM and 40 MPH after I trimmed up the motor to approximately the 1/2 mark on the gauge.  Without trimming the motor I can't get above 5000 RPM's.


i'm not real experienced with a high HP pontoon as I just traded up from an old aqua patio with a 50 HP.


do you guys usually trim up the motor to gain max speed?


what is a safe amount to trim up without causing issues?
Click to expand...

I can be trimmed down with a similar set-up and still hit 38-39WOT. When I trim up from there I can get to 42-43. Something is not right if your RPM that low when trimmed down.
 
maybe see about moving your motor up one hole in the transom? Someone did that recently and gained couple hundred rpm and 4-5 mph.   
 
I find my best top speed comes when I'm about 1/4 from the top (If that makes sense) and sometimes a little more depending on load. I considered moving the motor up one but wasn't sure on technique. Would a floor jack and a 4x4 work for lifting and raising at the mounting plate? Seems like a quick adjustment in the driveway while on the trailer.
 
lakeliving said:
I find my best top speed comes when I'm about 1/4 from the top (If that makes sense) and sometimes a little more depending on load. I considered moving the motor up one but wasn't sure on technique. Would a floor jack and a 4x4 work for lifting and raising at the mounting plate? Seems like a quick adjustment in the driveway while on the trailer.
Click to expand...

Not quite that simple. Raising it actually involves removing the motor from the transom. I raised the motor on my previous Bennie, so this comes from experience.


On the black and shiny motors, after removing the cover, one will find a lifting ring affixed to the engine block. I hooked a chain fall to an overhead beam (similar to what you would lift an engine from a car) to support the motor as well as provide the slight amount of lifting needed.


It's also important to know that the transoms (at least on a 2010 R-series, 2 tube) have treated plywood sandwiched in between aluminum sheeting. That means you will be leaving the old holes open and these need to be sealed with silicone caulk afterward.


So yes, it's not really a driveway job unless your driveway has an overhead beam for lifting. Let me know if you have further questions.
 
Joachim said:
turns out I was mistaken on the prop size.  It's actually a SDS Reliance 14 1/2 x 15.
Click to expand...

Does anyone make a 14 pitch prop for the Yammy? That might be your sweet spot. I think a 13 will be too little pitch, but it can't hurt to experiment.
 
goldnrod24 said:
Not quite that simple. Raising it actually involves removing the motor from the transom. I raised the motor on my previous Bennie, so this comes from experience.


On the black and shiny motors, after removing the cover, one will find a lifting ring affixed to the engine block. I hooked a chain fall to an overhead beam (similar to what you would lift an engine from a car) to support the motor as well as provide the slight amount of lifting needed.


It's also important to know that the transoms (at least on a 2010 R-series, 2 tube) have treated plywood sandwiched in between aluminum sheeting. That means you will be leaving the old holes open and these need to be sealed with silicone caulk afterward.


So yes, it's not really a driveway job unless your driveway has an overhead beam for lifting. Let me know if you have further questions.
Click to expand...

I wouldn't need new holes in my transom as the Yamaha has multiple holes and grooved slots where it goes up and down using the existing bolting location. I essentially would need to remove the two top bolts and loosen the bottoms, then just lift up. Are Merc's not setup like this?
SAM_3583_zps015d1ac5.jpg
 
I had to remove 4 bolts, raise the entire motor mount and put the 4 bolts into the new holes in the mount. No new holes in the transom.


So my comment about sealing the holes was incorrect. The same hole needs new sealant to prevent water intrusion.
 
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