Zero Off vs Z-Box

[whitecaps]

I own a SN 196 with GT-40 engine and Z-Box latest version. I also ski behind a SN200 with Zero Off. I'm not a short liner as 28 off at 32 mph is where I'm at. My questions 1.- is there an appreciable, noticeable difference between zero off and my z-box? Both systems are gps and mapped to our course, both have same options for pull type settings. My opinion is that I perfer the wake on my SN196 and seem to not be hammered by the pull of zero off. Course times are measured on both systems and are within allowance. 2. Other than the Z-Box not being approved for tournaments, am I hurting my progression by skiing more behing the 196 with z-box?

[whitecaps]

Thanks Gloersen, How about question 1. Is there a noticeable, appreciable difference in the two pulls? Seems like if both make approved times then there shouldnt be that much difference.

[Bdecker]

@whitecaps - I ski ZO almost exclusively, but at the end of each season I bring the 05 197 with zbox down from the big public lake course to the pond to give it a rip. I’m sure there are some very minor differences, but honestly I don’t notice them any more than the differences from one ZO boat to another. It’s not the real thing, but if you want to get close without replacing your boat the folks at perfectpass have done a very good job in my opinion.

[bishop8950]

I go back and forth ZO to PP every winter. I find there is a substantial difference between the systems. If you run PP with the ZBOX it’s closer to ZO but still different.

 

As @Gloersen said, if you are a tournament skier, and find the ZO boats feel different, then training behind PP will hamper your tournament results. But you can still progress your skiing very will behind PP boats, as most of us did for many years.

 

 

[eleeski]

ZO rocks! If you set up the Zbox just right, you can do well in tournaments. But it's a challenge. The Zboxes I've skied feel quite different.

 

PP Classic with a switch and KX-, PX10 felt pretty close to ZO. But it did take a savvy driver.

 

PP with a paddlewheel is great for tricks. ZO is also great (on "C" settings). Any PP without a paddlewheel or in wakeboard mode or RPM mode is unskiable.

 

When it gets down to it, it's the skier - not the speed control. Get the time on the water. Get a new boat when you can.

 

Eric

[LeonL]

@whitecaps if you ski with both systems, do you see an "appreciable, noticeable difference"? Your own experiences count for more than someone else's opions.

[bojans]

I am also not a short line skier and would regularly ski behind ZBox (primary) and ZO (2 puck) on occasion. I could feel the difference between the 2 but it wasn't a huge change and was able to adapt quickly. What really threw me off was going to tournaments and getting behind a single puck ZO. I felt that was a much bigger difference and harder to adapt to.

[DW]

@whitecaps : You will find a lot of discussion on this forum comparing speed control units, search feature will help you sort through them. There is a difference and it seems to depend on a variety of factors how much it is noticed by any given skier.

 

@eleeski : can you define 'savvy driver' and what that entails to match classic to ZO?

[eleeski]

The Savvy driver knows the wind and lake current adjustments to get the desired slalom times. To make PP Classic feel like ZO, I ran KX-, PX 10 with a working switch and set the baselines so I needed an extra 100 pounds of skier weight. Again, the baseline / weight settings are part of the savvy driving. I went about 3 years without noticing any score differences between PP Classic practice and ZO tournament scores.

 

Stan's boat had both ZO and Stargazer. I really struggled with Stargazer slalom - both in practice and in tournament. I spent some time with it as Stargazer was the speed control for Nationals. After that Nationals, I've avoided Stargazer.

 

I have only slalomed Zbox a couple times. In the class F tournament, everyone complained (including some Zbox skiers) so maybe something was wrong. It didn't feel right to me. But the Zbox skiers normally like their transition.

 

I love the feel of ZO. And how easy it is to drive. Even in an old American Skier!

 

Eric

[DW]

Got it, just was not sure where you were coming from on that. Thanks.

 

[BraceMaker]

I've been fiddling with tuning of PP for many seasons - how many of you have installed the newest PP software on the stargazer? I just got the chip a few weeks back and am about to upload it but will probably do some test runs before/after to double check.

[jhughes]

The latest Z-box software is a game changer. The set speed snaps in way, way faster than it used to and the auto-calibration feature is totally brilliant. Well worth the upgrade. As for a comparison to ZO, I have a Z-box boat and a ZO boat and the boats are so different (GT40 vs. 5.3DI, etc.) that it's really not a fair comparison. FWIW I'm really happy with the latest Z-box iteration. Great product.

[david_quail]

Slightly on topic - I just upgraded to z-box. I've never mapped a course and am curious what doing so actually does to the pull.

I know it times the run, but after mapping, is the boat also able to anticipate having to throttle up / down because it knows where in the course the skier is? Does it mean when free skiing, you have a lot more oscillation of speeds because it can't anticipate? ie. you lose a lot of the benefit of the z-box when free skiing?

 

After the upgrade I did notice a HUGE difference in how quickly and seamlessly it would snap into speed. And auto calibration was indeed dead easy.

[jhughes]

@david_quail it's just going to run a little hot (fast) because it's expecting a gate hit that it never gets as you free-ski down the lake. Essentially it's running in "pre gate" mode perpetually. Other than that no, it doesn't know where in the course the skier is, nor care, nor oscillate.

[david_quail]

@jhughes thanks!

So what exactly does mapping do then? Once it gets the gate hit it expects, it's able to manage rpms/speed with respect to the load the boat is receiving?

Sorry for simple questions :|

[jhughes]

Once it hits the gate, it's mission is to make a time such as 16.95s for 34.2mph over a gate-to-gate distance and do it segment by segment in the course generally as easily as possible taking input from the accelerometer, GPS, etc. and a million programmable parameters. The gate starts a series of measurements and times and magic so that the system does its best to make a perfect time in the gate-to-gate total length, based on pull type and whatnot. Outside of the "course" it's still going to do what it can to manage the speed but isn't concerned about making a specific time for a specific distance.

[WBLskier]

I have been super happy with my zbox. Latest software.

[DW]

@jhughes : Do you know if the 'pre gate' speed can be tuned for open water skiing? Always use PP control and do both open and course skiing so want ability to have both scenarios run at correct speed.

[jpattigr]

I also ski behind a new Prostar ZO boat (awesome) and my own 196 Z-Box (awesome) boat's. I like both pulls a great deal and ski very close to the same behind both. However last summer, I was skiing into 32 off behind the 196 at my cottage but when I can home and skied at the club was losing a full pass. At the end of the year, I discovered that my "new" mainline rope at home was mislabeled and was missing the 15 off section, thus my opening 22 off pass was actually 28! Always measure and check a new rope!

[jpattigr]

PS, I upgraded my Z Box last year to latest software and it was big improvement! Works great!

[jhughes]

@DW I think that's what the Simple Slalom mode is for, just basic open water skiing.

[BraceMaker]

@jhughes - I'm looking forwards to trying that when I do my install - but does it use accelerometer function of Z-Box or not?

 

Historically I would usually switch to RPM slalom on stargazer for free skiing/pulling new skiers, but then it is way more adjustment to z-box and zo. If simple slalom mode uses accelerometers in free skiing I'm going to run that way.

[jcamp]

My Z-Box has worked flawlessly and has really helped my skiing in tournaments. I cannot feel a difference between it an ZO and neither can my ski partner.

[whitecaps]

Correct me if I'm wrong but it seems both use gps accelerometers, both map/anticipate the course, both control RPM of engine, both are adjustable as to how the rpm boost is given(pull type). The only difference I see is that zero off contols rpm via the ECM whereas z-box does it via the throttle body on fuel injected in engines.

(I can see that z-box on a carb engine would in fact have a lag time that could be appreciable.) But on fuel injected engines it seems throttle control would be just as instantaneous whether the input is from the throttle body or the Ecm. Thoughts???

[eleeski]

My 04 MC had PP that worked great with the servo adjusting the throttle cable position at the throttle body. As noted earlier, I was able to mimic ZO with careful choice of settings. Note that this did involve the switch which was the old school version of electronic accelerometers.

 

The drive by wire boats never seemed to interact nearly as well with PP. I'm not sure what the interface was but the UCSD kids never built the servo throttle control we discussed to solve the problem on their boat. The lawsuit settlement and dominance of ZO ended the issue for all but a few boats.

 

Also note that the ZO engine in my American Skier has the electronic throttle on the engine and would easily adapt to the PP servo.

 

Personally, I don't think tiny time differences in response time will be noticed in the real world. Certainly not more than changing a number or letter. The proprietary programming will be the real difference. PP has to match ZO without reverse engineering the ZO. A difficult project that from the above reviews is finally working.

 

Cool, because the electric boat project (way off in the future) will be much simpler with the PP servo.

 

Eric

[DW]

@whitecaps : what is your reasoning relative to carb to FI reaction or lag time?

[whitecaps]

@DW : my reasoning is based on the properties of a carb delivery of fuel air mixture vs fuel injection. A carb is dependent on a mechanical accelerator pump to deliver whereas a fuel injection system delivers a pre prescribed fuel that is not subject to a mechanical device that has time lapse properties as a result of its design. Most agree that fuel injection systems are more responsive with a more linear power/acceleration curve. I'm no expert so this is solely my own hypothesis. I'm sure it has faults.

[DW]

@whitecaps : depending on type of FI unit, both depend on the actuation of the throttle plate, so response is depended on throttle plate distance from combustion chamber (assuming same pressure depression across the throttle plates). DI does change the game as does boosting.