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Discussion Starter #1
I recently purchased a Fantom dyno and am not clear on what it's actually telling me.

I've read through many of the threads dealing with motors and motor tuning and have Big Jims motor black book.

I was hoping I could get some help understanding the information that is presented by not only my dyno but other models also.
 

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Snuffy...

I'm not sure I can help you much... I have very limited experiance with Fantom dynos...

I've got lots of experiance with the Robitronic Dyno, and a fair amount with the Competition Electronics dyno.

I'd love to understand the Fantom dyno better. Right now I'm quite confused by some of the numbers that people give from the Fantom. To me, they often seem to disagree significantly with both the CE TurboDyno and the Robitronic. I mean this in a very general way, because there is almost no way to directly compare the numbers from one dyno to another, perticularly when the dynos are differnt manufactures. In a general way I basicly always see the same thing when I compare dyno data on my Robi to the data I get from the CE TD. The numbers are a differnt, but the slope of the curves at least consistantly go in the same directions when you make changes to the motors being tested.

If somone with a Fantom dyno could post some actual data that some of us non Fantom users could view, maybe we could get a better handle on what the differances are, and possibly figure out why they occur. If anyone does have Fantom data they'd like to share, I would be willing to put it up on one of my web pages... (basicly I have almost unlimited space, and bandwidth... at a low monthly fee that I pay out of my own pocket, it's a non comercial site, no banners or advertising) So... I'm offering a place to put it, all you'd have to do is get it to me... Hank is probably also willing to put up some data, but I can't speak for him...
 

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Discussion Starter #3
I have some data. I try to save my pulls but don't allways. What are you looking for? The time based sheet? I don't really know what to send.

Also, I and possibly others would like to gain an understanding of what the CE and Robi numbers mean. They all spit out data, if you don't understand what the data means it's a useless tool. It was not my intention to limit this discussion to only the fantom dyno.
 

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The single most common view I use is when showing the data in relation to AMP input. If the Fantom can display data in this format, I would like to see it for a few motors, with some explination of what type of springs and brushes are in the motor, etc...

What I was really thinking about is the actual data files that the Fantom surely must save. The Robitronic dyno saves two files, one is some sort of propritary data, and only the Robitronic dyno can read it (as far as I know). The Robi also saves a text file that can easly be read by almost any program such as Excel, Word, or any simple text editor. If the Fantom has some files simmilar to this, they could be posted somwere where others could download them, and then use some Fantom demo software to view them. (Assuming Fantom has demo software that allows people to view files).


As for dyno data in general... I feel peak numbers in general are not all that helpfull. At least not unless you have the surrounding data to put it all into perspective. Peak RPM in perticular is almost worthless, unless it has some indication of power/effciency that is being produced at that point. Even then, it's not of much value, except possibly to help choose gearing.

Somewhere Pat Collins (I think that's the name) has a pretty good general description of how to use a dyno. It's mainly focused on the Robitonic Dyno, but I beleive the principles he sites are pretty much universal. I'll see if I can find a refferance to it... it really is good reading.
 

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There is a search facility here at Hobbytalk...

if you search for 'dyno data' there are quite a few topics simmilar to this one... one of them I starte contains the text that Pat Collins wrote that I spoke of earlier... it's about half way down on the following page...

http://www.hobbytalk.com/bbs1/showthread.php?s=&threadid=2424


I have never seen a whole lot of discussion about the Fantom. I think partly because Big Jim never really liked Fantom dynos, and I think some people may have felt intimidated and/or uncomfortable trying to discuss the Fantom here as a result. I for one really would like to understand the Fantom, because there are so many others that have them... At least I could have a reasonable chance of talking with Fantom users about motors if I understood their dyno data... So I'll take a look at the Fantom stuff you posted...

rcavenger also just posted some stuff on the Monster Motor topic... so data is starting to apear now...
 

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is there anyway to export data from the Fantom into a text file that Exel could read?

I'm going to have to do some house cleaning on my lap top if I hope to install the decosoft program... it may be a while before I can acomplish this... :(
 

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Ok... I downloaded and installed The Fantom Facts Machine software... I also downloaded and unziped a file called allData.abc, however when I attempt to open a file with the Facts Machine software, it doesn't see the file I unzipped...

WHat am I doing wrong?
 

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Never mind... I think I figured it out...


So if I understand this correctly... all fantoms dyno data gets stored in this one file? Is there a way to create smaller files? like say you had 6 dyno runs that were all related and wanted to save them seperately so you could send them to someoene else to look at?

Anyway... I'm starting to look at the data now...

Thanks.
 

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Discussion Starter #10
The windows version of the software doesn't allow that or I haven't found where it is in the program. I'm not sure about the dos version. I'll check on it.
 

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Actually I think it is there... but it doesn't work in my demo mode...


The data sure does look a whole lot differnt then the data on the Robitronic dyno... I'm still trying to make heads or tails of it.
 
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TMFU,
You can save individual motors with the "File Transfer" button in the "Files" tab under "Individual Motor Test Maintenance & Viewer" button. It seems that the File Transfer saves the Files in the "Old" format. Then under "File" -> "File Converter", you can add the motor into the big list. With this info, you could export the motors you wanted to save separately, then rename your "allData.abc" to something else, and import the files you wanted into a new "allData.abc". That would allow you to send only the files you wanted to someone else. I know its a little convoluted, but it would work.
 
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I compared all of Snuffy's motors to the Monster, and The monster does show to be better than any other motor that he has run, except for "RM". What does RM stand for?

Now I'd really like to see the exact same motors run through a Robi and a Fantom. That would be interesting.

BTW, Snuffy, Thanks a Ton. I've been waiting a long time to view data from a Fantom.
 

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Seperate issue/thing...

I've been trying to use the 'option' menu item 'post time based data to clipboard' so that I could transfer some of the data into excel... so far it keeps all I get is the same data over and over. That is, I can't seem to be able to get it to save the data I'm looking at to the clipboard, it just the only thing in the clipboard is for "2K2-08 1-1-02"... never seems to change... Is this because the demo version is cripled? or is it user error on my part? Which ever it is... can someone tell me how to do it, if it's possible from the demo version?

My ultimate goal is to view data in relation to amp draw... since that's what I'm most used to looking at...
 

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Now I did something, and I no longer have anything in my clipboard... how do you get a perticular motor's data into the clipboard?
 

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Here it is, sorry I lost the spread sheet described at the bottom, I will work on making it again (computer virus hit me last year).

The Robitronics dyno is a very nice piece of equipment and can be very useful to a knowledgeable user. The problem is that most people that I see using the Robitronics or any flywheel dyno for that matter just don’t know what to look for. Even the most experienced motor men can find themselves just staring blankly at a screen with tons of data not knowing what to do with it. Big Jim Greenemeyer prefers the Competition electronics dyno because it tells him the information he needs without the clutter of too much information.

Many neophytes come on bulletin boards asking about the RPM of a motor, thinking this is what they need to know. Experienced racers try to tell them that is not really what to look for but they can relate to RPM the easiest. A semi-experienced racer knows it is power and not RPM that makes the car go, but many just look at the peak power produced which is only slightly better than asking what the RPM of a motor is. Most racers with the Robitronics dyno will tune their motor for the peak RPM, the maximum power, and the maximum torque numbers and total spin up time but do yourself a favor and don’t even look at these. They are next to useless believe it or not, more on this later.

If you are new to the Robitronics dyno I recommend using the view data screen on the menu to look at your data. Its fairly hard to relate the graphs to actual performance, even for the most experienced motor tuner.

I am going to limit the scope of this work to stock motors because they are what I have the most experience with. The most important thing about tuning a motor to perform on the track is actually knowing what you need the motor to do. Simply saying “I need a faster motor” can mean many different things. Often this statement doesn’t even have anything to do with RPM. By knowing what you need a motor to do you will have to approximate the amp draw of your motor in the situations that you feel that you need more power. If you constructed some type of speedometer you could work backwards and find the RPM range of the motor you also need more power, but I find that a good guesstimate will get the job done nicely.

Here are my guesstimates for 6-cell stock touring car and offroad racing. If you feel that you need some more out of the corner punch try to increase the power at 25 amps. For more of a top end feel shoot for maximum power at 15 amps. For overall “goodness” of a motor look at the power at 20 amps. And also the average power between 15-25 amps is a good indicator of the motors performance on track. If you tune to these parameters and feel the motor is a little soft coming out of the corners bump them up a few amps and try again. I stress again the importance of tuning a motor for the range that you are going to run it.

Now that I discussed what to look for when tuning a stock motor I am going to discuss the downfalls, shortcomings and quirks of the Robitronic dyno and its results. First lets discuss the peak power number and why it is not very important. Peak power is the power at one specific point in the power curve. When you are racing your motor is constantly changing RPM, even when going down a very long straight away. So you are probably lucky if you operate at one specific point 1/100th of the time it takes to make a lap. Secondly look at where peak power occurs, in stock motors running off 6 cells it is almost always at 35 amps give or take an amp. Just about the only time your stock motor draws this much current is when you peg the throttle coming off the line. In my experience in offroad and stock sedan a 20 amp average amp draw is fairly typical.

Although I find the peak power number fairly useless, using it is not all that bad the next mistake is far worse. Tuning for the peak RPM is just about the worst mistake that a motor tuner can make. The flywheel dynos load is provided by the acceleration of the flywheel. When the flywheel has reached maximum RPM the load is very small because the acceleration is very small. The power required to keep a flywheel spinning at 30k RPM is only a few watts. However when a car reaches maximum speed there is rolling resistance between the tires and ground, wind resistance and mechanical resistance in the drive train holding the car back. One day I may design a flywheel dyno that also has some sort of braking resistance so it provides the best of both worlds.

Spinup time can be somewhat useful in determining how quickly the motor can pass through its entire power band but it can also be quite misleading and I recommend that most people avoid using this number because its redundant if you use the power numbers to your fullest advantage. I say spin up time can be confusing because you can have two motors with virtually identical power bands where motor 1 takes 8.13 seconds total spin up time and motor 2 takes 5.84 seconds spin up time. (See the picture) You will notice that on motor 2 all of the extra time it took to spin up was at the very end of the power curve. Remember from before that it is impossible to get a motor in a car to operate in this range anyway, so this tells us that this extra spin up time reported by the dyno doesn’t mean a thing! You can check the elapsed time that it takes a motor to accelerate from a 30 amp draw to a 20 amp draw and use this number, but that is a fair amount of work and again it is redundant.

To figure out how much total drag is on a car find out its speed and you can work backwards to get the RPM of the motor at this point. Then you can find out the wattage the motor puts out at this RPM and viola, that is the drag of your car at maximum speed. I have created a spreadsheet to calculate the rollout, the tire RPM and motor RPM using your car’s speed, tire diameter and gear ratio. (attached).
 

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Discussion Starter #18
TMFU,

I think posting Time based data to the clipboard only works when you actually dyno a motor.
 

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I would really like to see this spreadsheet if you can find a copy. I was working on something similar... stymied for lack of data on drivetrain and rolling resistance. Drag is actually pretty easy, just pick Cd of 0.5 and area of 30 inches and it's pretty close.
 

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Discussion Starter #20
TMFU,
I stand corrected.

With the Save Time Based Data to the clipboard option checked, Open a motor test and go into the time based data. It is automaticly coppied to the clipboard. Just paste it into the program of choice.
 
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