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24' SXP with 200 hp speed/performance concerns

Vikingstaff

Vikingstaff

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First, I want to say we are pretty happy overall with our new Bennington.  We think it looks GREAT, and have enjoyed it the few times we've been out on it. I have a couple minor issues to bring up with the dealer when I take it in for its 20 hour oil change and service, but nothing major except for one performance concern: it is running slower than expected.


Details:


Currently I am still in the first 10 hours of the break in (8.4 hours precisely).  As many know, it is a 24' SXP Swing back SPS tritoon, with a 200 hp Mercury Verado Pro.  I have a ss Mercury enertia prop.  The dealer went with an 11 pitch prop. I thought it sounded a bit small, but they said it would put me in the proper rpm range, particularly when we have a fair amount of people on board. I had thought it would be a 13 or 15 pitch prop based on articles, posts, and the mercury prop selector site, but don't know much myself other than things I've read.


Current Performance:


With a half tank through full tank, riding solo or with one other person, I am topping out at 33-36 mph gps at 6200 rpm.


With a half tank through full tank, 4-5 passengers, I am topping out at 29-30 mph gps at about 5700-5800 rpm.


Expectations:


I really thought I would be somewhere in the 40-44 mph range top end speed. Keep in mind, this is early break in, so times at WOT are short and per the manual. I test drove a sweetwater premium last fall with 3 people on board and 150 Honda and got up to 38 mph on gps.  Thus, this experience also is impacting my expectations on our new boat.


From a performance expectations stand point, I am dissappointed.  I wanted to check with the more experienced owners out there with a similar boat and engine set ups and get feedback:


Is this level of performance just because the engine is new and in its break in period, and top end mph will get better after its broken in?  Were my expectations not realistic, and my numbers above are what I should have expected?  OR is it sounding like the boat is underperforming and I might need to look into issues such as a different pitch prop?
 
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6200 seems high. What's the recommended rpm range on that bad boy? I would for sure try a 13 pitch.


Props are a funny thing. I went from a 13 to a 15, my rpms actually went down and my speed went up 5 mph.


Don't despair, your sweet spot is out there, you just haven't found it yet.


PS: I'm gonna move this over to the props and power section.
 
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Agree with GoldenRod as I would expect a little higher MPH.  Really can't compare with other manufacturers, has a lot to do with weight and toon design
 
Assuming that's the 4 cylinder Verado, not the 200 Pro which is an I-6, that comes out to ~22% slip which seems fairly high. Max RPM is 6400, so there isn't a lot of room left either. I don't think break in will make any difference in speed, maybe 50-100 rpm/1 mph at most. Seems like it should be able to turn a lot more than an 11 pitch prop, so something doesn't seem right.
 
Vikingstaff said:
First, I want to say we are pretty happy overall with our new Bennington.  We think it looks GREAT, and have enjoyed it the few times we've been out on it. I have a couple minor issues to bring up with the dealer when I take it in for its 20 hour oil change and service, but nothing major except for one performance concern: it is running slower than expected.


Details:


Currently I am still in the first 10 hours of the break in (8.4 hours precisely).  As many know, it is a 24' SXP Swing back SPS tritoon, with a 200 hp Mercury Verado Pro.  I have a ss Mercury enertia prop.  The dealer went with an 11 pitch prop. I thought it sounded a bit small, but they said it would put me in the proper rpm range, particularly when we have a fair amount of people on board. I had thought it would be a 13 or 15 pitch prop based on articles, posts, and the mercury prop selector site, but don't know much myself other than things I've read.


Current Performance:


With a half tank through full tank, riding solo or with one other person, I am topping out at 33-36 mph gps at 6200 rpm.


With a half tank through full tank, 4-5 passengers, I am topping out at 29-30 mph gps at about 5700-5800 rpm.


Expectations:


I really thought I would be somewhere in the 40-44 mph range top end speed. Keep in mind, this is early break in, so times at WOT are short and per the manual. I test drove a sweetwater premium last fall with 3 people on board and 150 Honda and got up to 38 mph on gps.  Thus, this experience also is impacting my expectations on our new boat.


From a performance expectations stand point, I am dissappointed.  I wanted to check with the more experienced owners out there with a similar boat and engine set ups and get feedback:


Is this level of performance just because the engine is new and in its break in period, and top end mph will get better after its broken in?  Were my expectations not realistic, and my numbers above are what I should have expected?  OR is it sounding like the boat is underperforming and I might need to look into issues such as a different pitch prop?
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You're not propped right that is to small. I would suggest with your set-up should be a strong 39-41 MPH boat. When  I had 6 adults, coolers and ski equipment, I could still hit 38-40 MPH. Mine was  a 200 Yamaha but I would suggest that the mercs are ususally a little faster. 
 
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I had a 15 pitch Reliance on my 200. 
 
Sounds like your expectations are reasonable to me. I have a larger R25 that is definitely heavier and my Evinrude 200 HO pushes it to 41mph. As already stated,you need to find your sweet spot. Make sure you let your dealer know about your dissatisfaction with the performance. Ask to try different pitches till you get there.
 
Hey Jeff: My dealer insisted they had tried several props on my boat and picked the best performer. I didn't believe that to be true and told him so. They offered to sell me a 15 pitch prop to experiment with and I could return either prop (undamaged) for a full refund.


I gained 5 mph with the 15, so the 13 was returned and my credit card refunded, inc. tax.


Keep that option in mind in case your dealer is less than cooperative (which I doubt will happen).
 
Vikingstaff said:
First, I want to say we are pretty happy overall with our new Bennington.  We think it looks GREAT, and have enjoyed it the few times we've been out on it. I have a couple minor issues to bring up with the dealer when I take it in for its 20 hour oil change and service, but nothing major except for one performance concern: it is running slower than expected.


Details:


Currently I am still in the first 10 hours of the break in (8.4 hours precisely).  As many know, it is a 24' SXP Swing back SPS tritoon, with a 200 hp Mercury Verado Pro.  I have a ss Mercury enertia prop.  The dealer went with an 11 pitch prop. I thought it sounded a bit small, but they said it would put me in the proper rpm range, particularly when we have a fair amount of people on board. I had thought it would be a 13 or 15 pitch prop based on articles, posts, and the mercury prop selector site, but don't know much myself other than things I've read.


Current Performance:


With a half tank through full tank, riding solo or with one other person, I am topping out at 33-36 mph gps at 6200 rpm.


With a half tank through full tank, 4-5 passengers, I am topping out at 29-30 mph gps at about 5700-5800 rpm.


Expectations:


I really thought I would be somewhere in the 40-44 mph range top end speed. Keep in mind, this is early break in, so times at WOT are short and per the manual. I test drove a sweetwater premium last fall with 3 people on board and 150 Honda and got up to 38 mph on gps.  Thus, this experience also is impacting my expectations on our new boat.


From a performance expectations stand point, I am dissappointed.  I wanted to check with the more experienced owners out there with a similar boat and engine set ups and get feedback:


Is this level of performance just because the engine is new and in its break in period, and top end mph will get better after its broken in?  Were my expectations not realistic, and my numbers above are what I should have expected?  OR is it sounding like the boat is underperforming and I might need to look into issues such as a different pitch prop?
Click to expand...

I think according to your numbers you have more than a prop issue. If you're trimmed properly and your prop is an 11 pitch and you're only turning 6200 I would look at the motor mounting height, If the motor is mounted to low it will reduce your rpm's. My boat is larger and higher hp but I had this same issue, the dealer had a small prop on it to get the rpm's up because the motor was to low. My friends new 22S with SPS and a 150 Mercury runs 36 with 6 adults on board and half to full tank of fuel. I'm betting if you look your motor is mounted in its highest mounting holes which drops the motor to its lowest point. Just for a guideline every 1" of pitch is about 200 rpm's give or take on most any boat, more pitch=less rpm / less pitch=more rpm. Raising the motor one hole will gain about 100-150 rpm's. Here's a quick rundown of my setup from the beginning when I picked it up new, all numbers half to full tank of fuel


motor at lowest point, 15 pitch enertia prop rpm's  6400-6450 and 50.5mph


raised motor 2 holes, 16 pitch enertia prop on rpm's 6480 and 52.5mph


Full fuel, motor still up 2 holes, 17 pitch enertia prop, rpm's 6250 and 53.8mph


As you can see I clearly gained a little over 3 mph and I feel safe saying I gained 4mph because the final run was completely full of fuel and on rough holiday weekend waves so I expect to see 54 next time out.
 
Vikingstaff said:
First, I want to say we are pretty happy overall with our new Bennington.  We think it looks GREAT, and have enjoyed it the few times we've been out on it. I have a couple minor issues to bring up with the dealer when I take it in for its 20 hour oil change and service, but nothing major except for one performance concern: it is running slower than expected.


Details:


Currently I am still in the first 10 hours of the break in (8.4 hours precisely).  As many know, it is a 24' SXP Swing back SPS tritoon, with a 200 hp Mercury Verado Pro.  I have a ss Mercury enertia prop.  The dealer went with an 11 pitch prop. I thought it sounded a bit small, but they said it would put me in the proper rpm range, particularly when we have a fair amount of people on board. I had thought it would be a 13 or 15 pitch prop based on articles, posts, and the mercury prop selector site, but don't know much myself other than things I've read.


Current Performance:


With a half tank through full tank, riding solo or with one other person, I am topping out at 33-36 mph gps at 6200 rpm.


With a half tank through full tank, 4-5 passengers, I am topping out at 29-30 mph gps at about 5700-5800 rpm.


Expectations:


I really thought I would be somewhere in the 40-44 mph range top end speed. Keep in mind, this is early break in, so times at WOT are short and per the manual. I test drove a sweetwater premium last fall with 3 people on board and 150 Honda and got up to 38 mph on gps.  Thus, this experience also is impacting my expectations on our new boat.


From a performance expectations stand point, I am dissappointed.  I wanted to check with the more experienced owners out there with a similar boat and engine set ups and get feedback:


Is this level of performance just because the engine is new and in its break in period, and top end mph will get better after its broken in?  Were my expectations not realistic, and my numbers above are what I should have expected?  OR is it sounding like the boat is underperforming and I might need to look into issues such as a different pitch prop?
Click to expand...

Hi Vikingstaff,


Sorry the performance is not up to your expectations. We run fairly similar boats, obviously different brand motors but they have similar gear box ratio etc. I have the "small block" 200hp evinrude and I've been thru multiple props trying get the boat right where I want it. I probably gave up a MPH or so but I'm pushing a 15 pitch Rebel 40.3@5350RPM right now . I run my motor in the 3rd hole meaning I only have one more to raise it. (25" shaft). I can easily push a 16 pitch prop (viper) 42.1@5200RPM but that prop sucks fuel and is horrible for tubing. These numbers are just me and the wife, always keep the tank full. When we have guests even with 7-8 people we don't tend to run much less then 37-38MPH when everyone wants the wind in their hair. :)   Lake Living is running a 200hp Yamaha w/matching boat and he's pushing 44MPH which I would assume you would be comparable to. I ran the Mercury prop selector and with a 15 pitch @ 6100RPM they're claiming 46MPH??? Giving Lake Living a run for his money!! I'd talk the dealer into a few props to try or talk to Ken at Prop Gods and take his recommendation. Running anything less than a 15 pitch is only going to be disappointing!!
 
I agree with the above that you are absolutely running the wrong prop. I run a reliance 15 and JTaylor on here with the same setup is running a 17 if I'm not mistaken. My motor is also mounted all the way down. I am really really considering raising it one hole to see what it will do. Maybe I can hit that 46 ADK is talking about!!! Plus my rpm's are a little over 5800 so I have some room to get it up higher to the 6k max.


But hang in there. I remember posting something after getting mine that I was not getting good results. Turns out I was a noob and needed to trim higher than I thought I should.
 
I have the 25 GSB with SPS which should be a little bit heavier than yours, I am running the evinrude 200 HO like builderbob with a 15 3/4 x 15 SS rebel.  With 2 people on board I am seeing 45-46 at 5200 rpm.  With 6 adults and a full load, getting 42 mph.  My expected full throttle range is 5200-5900 rpm per Evinrude and this prop barely gets met to 5200 so I am considering trying a different pitch. 
 
So glad I posted this concern. I knew there would be lots of good insight and advice!!!


I had not considered what hole the engine is mounted on/in.  I will be taking a look at that this weekend, and stopping in to talk to my dealer. If I am mounted with the engine all the way down, I will bring up raising it up to see what that does. 


I am also going to discuss a prop change.  I think I will ask about trying the 15 pitch ss Mercury enertia prop.  If they insist on the one I have, or that I need to buy a different one to test out, I will run Randy's idea by them for testing different size props.


I was pretty certain my performance was off, and my expectations were reasonable.  Sounds like I will get there, but it will just take some experimentation.  


I have free dockside service for one year, so I am assuming they can change the prop out right at my dock.  However, my guess is they will need to take the boat in to remount the engine in different holes.  


Assuming that is true, should I try to pin down my prop now, and just wait on the engine mounting until I take it in for its 20 hour oil service OR should I be doing the prop and engine mount at the same time?
 
TomS said:
Assuming that's the 4 cylinder Verado, not the 200 Pro which is an I-6
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I have the 6 cylinder Verado Pro I-6 200 hp engine.  I am assuming that changes the numbers and thoughts, but thought I would clarify.
 
The engine height and the prop will go hand and hand. The prop you can change on the water, the engine they'll want to pull it out to adjust. Just make sure you don't make a ton of changes at one time, if something doesn't work you'll have no idea what the issue is. Start with the prop and then height adjustment. Search the forum about engine height and once you change the prop take a look at the boat underway and see how much you may need to raise it. Remember you'll gain some Rpm raising the motor. 


Drive it like you stole it!!! :)  
 
adkboater said:
The engine height and the prop will go hand and hand. The prop you can change on the water, the engine they'll want to pull it out to adjust. Just make sure you don't make a ton of changes at one time, if something doesn't work you'll have no idea what the issue is. Start with the prop and then height adjustment. Search the forum about engine height and once you change the prop take a look at the boat underway and see how much you may need to raise it. Remember you'll gain some Rpm raising the motor. 


Drive it like you stole it!!! :)  
Click to expand...

Sounds good.  Kind of like a food allergy with a kid.  You got narrow it down one item at a time.  I will work the prop end of it initially.  For all I know, that might take care of the issue all together.  If not, I can then examine the engine mount. 


Thanks Everyone!
 
Vikingstaff said:
I have the 6 cylinder Verado Pro I-6 200 hp engine.  I am assuming that changes the numbers and thoughts, but thought I would clarify.
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Oops, my calcs were a bit off then. The I-4 is 2.08:1 gear ratio, but the I-6 is 1.85:1 gear ratio.
 
Plugging in 1.85:1, 6200 rpm, 11 pitch, and 32 mph is ~8% slip, which would be quite good. That said, an 11 pitch should allow that motor to spin WAY more than 6200 rpm.


Also, be sure to follow the break in procedure, which says use full throttle for short periods. You will NOT hurt the engine doing this.
 
TomS said:
Plugging in 1.85:1, 6200 rpm, 11 pitch, and 32 mph is ~8% slip, which would be quite good. That said, an 11 pitch should allow that motor to spin WAY more than 6200 rpm.


Also, be sure to follow the break in procedure, which says use full throttle for short periods. You will NOT hurt the engine doing this.
Click to expand...

Thanks for the updated information! Interesting on the rpm part of it.  Would that be indicative of being mounted to low then, maybe stymieing RPM's...?


I've been following the break in procedure precisely - using my phone stop watch and all. I was precisely 1 min at WOT for every 10 minutes on the water at variable throttle under 4000 RPM's for the first two hours.  I have been at variable throttles across the board and no more than 5 minutes at WOT for hours 3-8.4 so far. I am 1.6 hours away from finishing break in and driving as I please.  


I also plan to do the full oil change and service inspection at 20 hours. This will be our baby for a long time, so we want to make sure we do it right.


Thanks so much for your insight and observations so far.  It's very helpful to someone like me that is totally new to boat ownership.
 
I've not seen numbers quite like this before, even the prop slip calculator seemed puzzled by it. It seems like the motor isn't making enough power or there is a ton of drag. With the lighter S structure and SPS package that thing should fly. Have you looked at how deep the cavitation plate is in the water at cruise speed? It's not necessary to be WOT for this, just planed out flat.


Here is a good video on the topic:


Verado engine height
 
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