2012 212SS can't get both engines to equal RPM under WOT

[Michael Lewis]

Under WOT conditions, my port engine achieves 7600rpm and my starboard engine achieves 7400rpm. What can I do to get both to 7600 or better yet the redline as I understand it 7700rpm?

PS. I did remove the ribbons and this didn't help with top rpm but the hole shot is noticably stronger. And yes this mismatched rpm issue was present before removing the ribbons. Also air filters are OEM and clean, and my plugs are good because the engines idle well and have very good power bands.

 

[Rooster]

Adjust throttle cables?

 

[Michael Lewis]

Adjust throttle cables?

It's a drive by wire system so I didn't think adjusting the throttle cables would help.

 

[Rooster]

I'm almost positive you have the same setup as my 2018 212LS, mechanical cable controlling a box on the wall of the engine bay that is throttle by wire.

Sorry if I'm wrong but I found this post to be helpful when I had a similar issue

https://jetboaters.net/threads/rpm-big-difference-twin-engines.5586/

 

[zipper]

On my 07, I had to split the throttles to get the engines to sync thru the rpm range. Most likely attributed to the difference in impellor pitch and loading between the two jetpumps. One was about 200rpm's higher than the other. No drive by wire on these. Throttle linkage's connected to throttle body on each engine.

 

[FSH 210 Sport]

I had this same issue on my 2020 210 FSH Sport. The OEM impellers are identical, the miss match in rpm’s at wot is caused by the difference in loading of the pumps due to the fact, at least this is what I believe, that both screws are turning the same direction. Most all twin engine set ups have one prop that is turning the opposite direction from the other, this keeps the torque steering negated, and that’s why your boat turns sharper to the left than the right.

The older boats from what I understand had two different pitch impellers to compensate for this. On my high altitude impellers, Glen at Impros varied the pitch slightly. I think slightly more pitch on the port engine to keep the loading and rpm’s the same. I also had Glen “match” my OEM impellers the same way to get the rpm’s the same which gives a little more bite on the port side. In lieu of having the impellers “matched” you just have to slightly split the throttles at wot to get the engine rpms synched.

 

[biffdotorg]

Under WOT conditions, my port engine achieves 7600rpm and my starboard engine achieves 7400rpm. What can I do to get both to 7600 or better yet the redline as I understand it 7700rpm?

The follow up question is, why? OCD? 200rpm is not much difference. And very normal.

I have a throttle sync on top of my sticks and still find myself twisting the two handles to sync them up only if to match the sound. They sound so good when synced. I can hear it before I see it on the tachs. But for me, it truly is just OCD. And it only happens at high RPM's. Cruise assist helps as well.

And no a 2012 is not considered a true throttle by wire system, as there is some adjustment of the cables near those boxes. Will Owen posted a video of how to adjust them on the Jetboat pilot site.

 

[Michael Lewis]

The follow up question is, why? OCD? 200rpm is not much difference. And very normal.

I have a throttle sync on top of my sticks and still find myself twisting the two handles to sync them up only if to match the sound. They sound so good when synced. I can hear it before I see it on the tachs. But for me, it truly is just OCD. And it only happens at high RPM's. Cruise assist helps as well.

And no a 2012 is not considered a true throttle by wire system, as there is some adjustment of the cables near those boxes. Will Owen posted a video of how to adjust them on the Jetboat pilot site.

YES it's OCD! lol. When I took the ribbons out I saw an electronic throttle body so based on that it seems to be drive by wire. At least some form of it. I'll look for the video. Yes I can get my throttles in sync based on sound but just wanted to see if I could get them both the same RPM but don't think that's possible based on what FSH2010 Sport said which makes sense. Also I have the issue where both throttle levers are out of alignment. It's always been like this from day 1 and is annoying. Hopefully the video you mentioned will resolve that too.

PS Does anyone know where I can find a reliable aftermarket tune for these engines?

 

[Michael Lewis]

I'm almost positive you have the same setup as my 2018 212LS, mechanical cable controlling a box on the wall of the engine bay that is throttle by wire.

Sorry if I'm wrong but I found this post to be helpful when I had a similar issue

https://jetboaters.net/threads/rpm-big-difference-twin-engines.5586/

You are probably right. I'll check into it further.

 

[biffdotorg]

YES it's OCD! lol. When I took the ribbons out I saw an electronic throttle body so based on that it seems to be drive by wire. At least some form of it. I'll look for the video. Yes I can get my throttles in sync based on sound but just wanted to see if I could get them both the same RPM but don't think that's possible based on what FSH2010 Sport said which makes sense. Also I have the issue where both throttle levers are out of alignment. It's always been like this from day 1 and is annoying. Hopefully the video you mentioned will resolve that too.

PS Does anyone know where I can find a reliable aftermarket tune for these engines?

I'm with ya, I'm glad you took my tone lightly, as I twist those things to get them synced as well, but it's not life or death. Now if you say they are out of alignment all the time, then yes, that is the adjustment you make. they are mechanical back to those boxes, and that is truly what you are accomplishing at that point.

Since they are EFI, yes, at some point it will go electronic. But this was a common practice to adjust those cables before installing a GPS speed control, like Perfectpass etc. As you want them as synced as possible, as the PP would take it from there.

As far as a tune, most don't touch that sort of thing, as the motors are performing at an optimal level for the pumps they were shipped with. Not much more and they will cavitate. They are so reliable, with better performance than other boats in their price range and category.

And even with the supercharged versions, with bigger pumps to handle it, the speed gain is minimal. That's why "tunes" are not as common with boats, as the juice is literally not worth the squeeze, unlike other powersports vehicles with a higher power to weight ratio.