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Top Speed RPM Question

I also bought from River Valley and got a CARB boat. On one hand its a great deal, on the other hand you get a CARB boat. I guess it all depends on whats the most important thing for you, the deal or 4mph... For me I finally succumbed to the fact that I hardly EVER run a WOT and I typically just cruise at 5500RPMs, so I'm not heartbroken and I love my boat. I guess if need be I can see about finding a way to gain those 4mph back thru performance mods such as a filter and maybe re-pitching the impellers.
 
I also bought from River Valley and got a CARB boat. On one hand its a great deal, on the other hand you get a CARB boat. I guess it all depends on whats the most important thing for you, the deal or 4mph... For me I finally succumbed to the fact that I hardly EVER run a WOT and I typically just cruise at 5500RPMs, so I'm not heartbroken and I love my boat. I guess if need be I can see about finding a way to gain those 4mph back thru performance mods such as a filter and maybe re-pitching the impellers.

I looked into the filter and the throttle ribbon removal if you are looking into that. The consensus here is that mod doesn't make a difference. I bought the filters, wrong ones, and the throttle body insert. I started taking the filter off and thought maybe it wasn't such a good idea. I think there might be warranty issues if you do the mod. I'm happy with my CARB boat. I've hit 48kts with it and that's pretty good. Like you, most of my cruising is around 5-6,000rpm and 25-30kts. The boat rides really well at those speeds. And when you start filling the boat with gas, I think you tend to drive a little slower.
 
I looked into the filter and the throttle ribbon removal if you are looking into that. The consensus here is that mod doesn't make a difference. I bought the filters, wrong ones, and the throttle body insert. I started taking the filter off and thought maybe it wasn't such a good idea. I think there might be warranty issues if you do the mod. I'm happy with my CARB boat. I've hit 48kts with it and that's pretty good. Like you, most of my cruising is around 5-6,000rpm and 25-30kts. The boat rides really well at those speeds. And when you start filling the boat with gas, I think you tend to drive a little slower.
I disagree. I believe the ribbon removal and filters make a difference. I instantly got another 200 rpm on the same day I did the change. I also believe the boat is more responsive. Take it or leave it. I'm happy with the upgrade.
 
Took my 2011 sx240 out tonight only hit 46mph as well. I didn't pay attention to the Rpms but that was with 8 people on board and 3/4 tank of fuel. Does that sound about right for a top speed?
For 8 people and 3/4 tank of gas that sounds about right. I bet the boat would do over 50MPH if you were by yourself.
 
I did the flame arrestor removal / replacement with velocity stacks / intake manifold upgrade on both of my yjbs (I.e., six 230 ho and 242 Ls). IMHO it's snake oil for anyone boating at or near sea level. That is, I did not see or feel any performance improvement after either upgrade. No boost in rpm at wot, no increase in top speed or acceleration, nothing. I think this has more do do with what rpm that Yamaha limits us to. At sealevel I can max the rpm to the rev limits set by Yamaha (10,200 for the sx and 7,700 for the Ls). If I boat at altitude say 5k feet or more up my engine does not rev as high and the performance suffers accordingly. This is just my opinion but I think the upgrade would help those that boat at altitude get more rpm and therefore more performance out out of each engine. At the same time it may be worth it for those on the fence to simply remove the stock flame arrestors to see what, if anything, changes. The air will not flow as smoothly as if velocity stacks or the manifold upgrade were installed but you won't spend $ 80 to $100 figuring it out either.
 
I did the flame arrestor removal / replacement with velocity stacks / intake manifold upgrade on both of my yjbs (I.e., six 230 ho and 242 Ls). IMHO it's snake oil for anyone boating at or near sea level. That is, I did not see or feel any performance improvement after either upgrade. No boost in rpm at wot, no increase in top speed or acceleration, nothing. I think this has more do do with what rpm that Yamaha limits us to. At sealevel I can max the rpm to the rev limits set by Yamaha (10,200 for the sx and 7,700 for the Ls). If I boat at altitude say 5k feet or more up my engine does not rev as high and the performance suffers accordingly. This is just my opinion but I think the upgrade would help those that boat at altitude get more rpm and therefore more performance out out of each engine. At the same time it may be worth it for those on the fence to simply remove the stock flame arrestors to see what, if anything, changes. The air will not flow as smoothly as if velocity stacks or the manifold upgrade were installed but you won't spend $ 80 to $100 figuring it out either.


With the "ribbon delete" your results may vary. It depends if you are already running at the rev limit or not.

For me, it made a significant difference after impeller upgrade - worked out great! I'm pretty much at sea level.

The boat was doing about 7600RPM and 43-44mph before. After ribbon delete (stock filter in) - hitting the rev limiter at 7800-7850RPM and the boat runs 47mph for as long as I want (phone GPS; boat speedo maxes out).

The ECU seemed to have automatically adjusted for the added air, and the boat feels MUCH happier, it is snappier and sounds better. The impeller is custom pitched Solas by Impros.
 
When you say stock filter, did you leave in the original filters and just remove the ribbon?
 
When you say stock filter, did you leave in the original filters and just remove the ribbon?

Yes, the original filter left in and just removed the ribbon (with the rubber seal). I must say, other than the impeller / wear ring upgrade - this was the best (un)mod I have done to date!

I plan to change the filter to the one from Island Racing (R&D POWER PLENUM FLAME ARRESTOR 200-01800 $139.95) to be in compliance with CG regs.
 
I'm coming from a world of skis so this may not apply to boats but it may. What i find most people due on skis when they are trying to improve performance is they get the ECU reflashed and this usually lifts the rpm restrictions and several other things giving you a high top speed. I know riva and vtech offer these on the 1.8 motors on the Yamaha skis has anyone ever tried it on a boat?
 
Today, calm water, sea level. 1/3 tank fuel. 4 adults 4 kids. WOT Left engine 7400+ change rpm Right engine 7200+ change rpm. 49MPH. 22gph
 
@Freezer41 , if you have a CA/CARB boat with catalytic converters your performance sounds about right from what I've read here and on YJB but there is probably a boattest.com video which reflects what their performance was.

@swatski , I have custom pitched solas impellers as well. My boat accelerates faster than it used to with stock impellers and my top speed appears to have improved a little as well (it didn't go down anyway but I realize its is hard to duplicate conditions between runs). I attribute that to the impellers not the manifold upgrade. I went with the standard aftermarket R&D air filters but recall someone using the power plenum in a 242. They (R&D or the reseller) had to trim a little of the mount to make it fit on one of the two engines, not sure which one, you may not have any issues with this on your boat but its just something to keep in mind.

@robert843 , I haven't heard of anyone flashing the stock ECUs in our boats but another member, @satovod , replaced his stock ecus with after market units, after this and a few other mods he got his 242 LS going 65+ MPH. I recall seeing the pics of the speedo which is GPS assisted. The problem , for me anyway, of getting aftermarket ecus is the cost, something like $3,000, each.
 
@Freezer41 , if you have a CA/CARB boat with catalytic converters your performance sounds about right from what I've read here and on YJB but there is probably a boattest.com video which reflects what their performance was.

@swatski , I have custom pitched solas impellers as well. My boat accelerates faster than it used to with stock impellers and my top speed appears to have improved a little as well (it didn't go down anyway but I realize its is hard to duplicate conditions between runs). I attribute that to the impellers not the manifold upgrade. I went with the standard aftermarket R&D air filters but recall someone using the power plenum in a 242. They (R&D or the reseller) had to trim a little of the mount to make it fit on one of the two engines, not sure which one, you may not have any issues with this on your boat but its just something to keep in mind.

@robert843 , I haven't heard of anyone flashing the stock ECUs in our boats but another member, @satovod , replaced his stock ecus with after market units, after this and a few other mods he got his 242 LS going 65+ MPH. I recall seeing the pics of the speedo which is GPS assisted. The problem , for me anyway, of getting aftermarket ecus is the cost, something like $3,000, each.

Will the aftermarket ECU's work on the CARB boats? Any idea what rpm increase the guy got with the new ECU's? I'd like a few more rpm's but I wonder how much more wear you'd get on the motors to get 65mph?
 
Will the aftermarket ECU's work on the CARB boats? Any idea what rpm increase the guy got with the new ECU's? I'd like a few more rpm's but I wonder how much more wear you'd get on the motors to get 65mph?

All I know is on the 1.8 engine on the skis you can buy a reflash for the ecu for about $600 to $700. Depending on the one you purchase is how much the rpm raise is. The basic model will move you up to 8250 rpm limiter the go as high as 10,000 rpms but require serious upgrades to the engine to handle that but also not sure you could achieve those rpms with out the super charger. The basic upgrade on the ski add 3-5 mph just with the reflassh. Here is a link to the basics you get.

http://ecunleashed.com/product/2011-yamaha-waverunner-fx-ho-2/
 
Here is a link to R&D's web site with pricing and options I also know VTECH makes these as well.

http://www.rd-performance.com/newproducts/yamaha/fxho2012.asp


Thank you, this is what I think I want to do. But none of these outfits advertise ECU flash service specifically for the boats...

I wonder though, if asking to raise the rev limit ONLY (by some 300-500 RPM or so) would be the way to go, as remapping across the entire spectrum with a jet ski algorithm may not be the best idea...
 
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Thank you, this is what I think I want to do. But none of these outfits advertise ECU flash service specifically for the boats...

I wonder though, if asking to raise the rev limit ONLY (by some 300-500 RPM or so) would be the way to go, as remapping across the entire spectrum with a jet ski algorithm may not be the best idea...
What I would do is either call vtech or R&D and ask them if they have one precoded for the boat as I'm not sure what the differences are. These guys are both pretty good and they may have something already mapped up and if not they seem to love a challenge and I bet one of them would be willing to map you something up. These are designed for our engines just in a different boat I'm just not how different the ecu is in the boat compared to the ski. The revlimiter stock seems to be the same on both and if all your asking is for that to be raised they likley would tell you to pull your stock ecu and send it them and they will do the adjustments to it.
 
They may want to just leave the timing slightly retarded until wot on our boats. In all reality, the weight of the boat has absolutely no impact on the engine.

Beauty of the jet pump!
 
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Well I have emailed R&D, VTECH and Riva. I will let you know what I hear. I have a feeling the Riva product will work as its very interchangable but it is also by far the most expensive.
 
Anyone have a pic of an ECU from a 2010-14 boat with a 1.8l engine? My boat is not here and one of the companies is asking for it.
 
Anyone have a pic of an ECU from a 2010-14 boat with a 1.8l engine? My boat is not here and one of the companies is asking for it.

I am at work and won't get out before dark, but can do it tomorrow morning on my SX190.

Very curious what they say.
 
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