dmilzoff

I'm looking to install an AIM MXL Pista dash in my 89 944S2.
I'm concerned about being able to install (or use existing) sensors that the AIM system can read.

Does anyone have experience in this dash and can help me out with the sensor needs?

David

95m3racer

I spoke with Frank today, if you have any other questions, feel free to have him ask me.

With the MXL, you can easily tap into basically any sensors on your engine, TPS, RPM, temp/pressures, etc.

Unfortunately, you cannot tap into any rs232/canbus port as our car is not compatible, so you'll have to tap into each sensor.

For the speed sensor, if you have ABS you can tap right into one of your wheel speed sensors, and just count the number of teeth, plug it in and you are good to go. You can run an independent sensor, or use the split cable and get two wheel speeds if you are interested, however for your application I don't think you'll need it. I'd just use a single speed off your drivetrain. I don't know how your car was setup specifically, but I think it still has the stock speedometer, so that sensor is most likely no help to you. If you can find out the details about the stock speedometer sensor, you might be able to tap off it. I believe its on your transmission, so it probably just reads off a gear, so you'd need to know how many teeth.

You can also run the new GPS module, and you won't necessarily need the wheel speed sensor, however I would highly advise a hardwired speed sensor, at least for gps verification.

You also have the option to go to DaVid, and monitor 5 inputs other than speed/rpm/laptime, but integrate real time video. I do not think you can run the MXL dash with the David (easily) but you can link the M3 dash to it. The other option is to use the DaVid Slave unit with the MXL Pista, but its a bit more money obviously.

For your DE and beginner club racing application, this is a GREAT tool.

I can help you understand and learn the software, and how to analyze this basic data...you can do TONS of analysis even with the most basic of inputs.

I'd also suggest a separate oil pressure backup gauge to keep on the dash, separate from the AIM. Just tap in somewhere else to monitor as a backup...cheap insurance. And since you have the stock fuel tank, unless you want to make a a small circuit to convert the resistance into a voltage the dash can read, just keep the stock fuel gauge visible.

mnorek

David,

I have the AIM system (I use an XG Log dash) installed in my BMW race car last year, and can confirm that it is an amazing piece of hardware. I had Conway Autoworks install the system, but it was not very much labor time. Oil temp, pressure and rpm are all taken from existing outputs. I added a water temp input for my car, but you may not need it. Lateral and longitudinal Gs are from accelerometers in the unit and speed is calculated from a sensor on a half shaft (you can do more, as stated above). The speed sensor was the only install that I could not have easily done on my own since it required welding a mounting bracket.

The only other input I have is the IR receiver for the laptimer. It is amazing how the computer can actually plot a track from the speed, distance and Gs. GPS would make it even better, but frankly, this much data is enough for now. I haven't calibrated it to show gear data, but that's easily done--I just haven't done it yet.

Go for it, it's a great system!

Michael

BrianKeithSmith

Gang:

I hope you don't mind if I hop in on this thread, but I too am considering the AIM MXL PRO (as well as the DL1).

I wanted to know what sensors/data you guys are currently collecting?

I'll start with a supposedly obvious list, but if you have any additional data you are capturing, I'd like to know, maybe you are capturing something I haven't considered. I want to pretty much start off with the basics, and expand over time (hopefully).

1. RPM
2. Engine temp/oil/water temp
3.Speed sensor (as mentioned normally on the halfshaft)
4. boost???
5. any sensors that trigger a light when it reaches a certain threshhold the you like to look at?

Thanks,

Brian

95m3racer

AIM MXL PRO is in an entirely different class than the DL1. MXL Pro05 is Substantially more powerful, and has a much larger range of possibilities.

Just a headsup in general...more sensors does not mean you get better answers, it just means you have more numbers in front of you.

Pickup one of the 3-4 DAQ books from a racing book store, and learn how to decipher what is what. For all amateur racing, unless you are developing a new chassis/suspension design, you are really just doing setup and driving training. That means your inputs needed are limited.

Accelerometers (2-3),Steering angle, throttle position, speed, rpm, thats a LOT of data. Throw in brake pressure/position, and GPS and you start to become bombarded with data and basically don't benefit, just are now at a disadvantage,

I actually think the video systems with overlayed data are the best b/c you can see whats happening and directly correlate what you did to what you should have done.

If you just want to monitor your engine, thats a different story.

Software is the key to all of this, and Aim's constant updates to software/firmware makes sure everything is always working together.

You will not benefit from all this fancy gadgetry if you cannot master the software and take full advantage of it.

924RACR

I'm actually not a fan of the video overlay for learning unless you've got a good camera location - it's hard to see much about line information, etc, with an internal (inside cockpit) camera angle. Roof cam, the only way to go.

Otherwise I agree with what 95m3racer is saying, pretty much. Though you may find the following presentation more helpful than the data acq books - it's purely focused on driver development for a beginner in data acq:
http://www.vaughanscott.com/AIM/Data_Analysis_Intro.pps

I still need to compile the notes from the presentation and make those available, but that's got all the key stuff. As you will see in there, the basics you'll need to start with a speed, RPM's, and g's (lat and long)... the added signals can come later, once you've learned how to use the above effectively.

One final note - if you plan to tap into the stock/existing speed sensors AND continue to use your ABS, be careful about tapping into those wires; if you introduce noise into the sensor signal (very common problem when messing with wheel speeds), you can either disable the ABS or make it work as not intended - inappropriate wheel brake control, can do ugly things (lock wheels, underbrake wheels, or turn the car unexpectedly!)!

As for the AIM system, I've been using it for quite a few years now (I have a lower model, the MyChron3 Gold XG) and am VERY happy with it. Wish I had more channels, but I make do with what I have.

Z06

Who sells these Aim systems with support help in instalation and set-up?
I need two systems, hopefuly I can get a deal as well...

924RACR

I've been very happy with the support and service here, though I bought my logger elsewhere:
http://www.motorsports-exchange.com/eStore1.htm

GeorgeNZ

re speed sensor mounting - there are a couple of M8 tapped holes on the lefthand side of the '44 transaxle above the CV joint - in my case, I bolted a short length of alu. angle to this and drilled the other flange to take the sensor. I used a small circular rare earth magnet from Jaycar (? US equiv) straight on the CV instead of the std pickup. I've only lost the magnet once on some big curbs. Fitting another is straight forward if you do lose one.

I've found brake pressure and throttle useful channels for identifying bad habits...........

Water temp probe can go into the bleed hole and I used a seperate sender for oil pressure - on a remote mounted Tee with the stock one.

With the MXl covering the speedo and tach, you can still see fuel and oilP gauges but it does obscure the stock general warning light.

Anyone with a cunning install for steering angle or feeding an input from the stock warning light to one of the alarm LEDs?

95m3racer

Vaughan, nice presentation, but I did see some small issues with it, nothing major though, very good entry level overview of what you can do out of the box with simple data.

You might want to update it for products that now use GPS, and have higher resolution.

Also, I would still highly suggest getting a book on data acquisition. Understanding the concepts behind the hardware/software is the important part. This is where good software comes into play though, because if you have to spend 2 hours on one program doing something it takes 5min to do on another, the choice is obvious.

Aimsport has some great "hidden" features built into their software that i'd say a good majority of users, never even have heard of, let alone take advantage of. The engine and suspension analysis tools built in are very cool, and with a tri-axial accelerometer setup (or just a CG, and roll center positioned) you can get some great information.

You really don't need shock pots unless you are developing valving characteristics, but you can use rotary/linear pots for height changes, or even ultrasonic height sensors if you have the $. You can use the chassis height changes fore/aft to determine dive/squat characteristics, and if you are developing higher level suspension, you can start to take advantage of shock pots on each corner for roll analysis.

Basically, even for a top level amatuer club racer, in almost all cases, you really just need to train the driver, the cars are on average much more than most drivers can take full advantage of. Nothing worse than a 600hp car with full race chassis/suspension setup, on big slicks, running sloooow.

As far as video overlay, I like what systems like DaVid does because you can see your hands/feet, and see whats happening to the car and how your input are affecting them. Its easy to correlate a video of the car understeering, to the data and you can see what happens.

Another benefit of the video is the sound. Tires/engine tell you a lot about the car, an element that is lost in pure data acq.

And another big benefit of the DaVid is you can use one or even both cameras to film chassis/suspension components, and SEE whats happening, and find out why something is happening. Maybe you have a push on exit when you get on the power...you put a camera down there and you see there is a part flexing under a certain load, and it creates this event, etc etc etc you get the point.

The biggest problem at this level of motorsport is deciphering what is a Driver issue and what is a car Issue. I have seen many cases where a driver reported a problem, engineers disagreed, another driver hopped in and proved with data (and lap times) the car was fine.

Caddell

The AiM products, both the MXL's and XG Log's mentioned here can accept user generated "custom sensors" of any sensor not already in the vast AiM sensor library. The sensor output just needs to have an output of 0-5v.

We used a MXL Pro '05 to win the SCCA Runoffs this past year in the Spec Miata class. We used the following sensors:

The normal... Speed, RPM, Laptimes, Oil pressure, Water temp, Lateral G's, Calc gear, Logger temp, Battery voltage. These are all included in a standard kit.

We then also ran: Steering position, Throttle position, Wide band Lambda, Brake pressure, Longitudinal G's, and Front wheel travel potentiometers.

Steering and Throttle are sensors that I would be lost without. With these and the "normal" channels above, we can determine what the car is doing and even more importantly if the driver is reacting to what the car is doing or is the car reacting to what the driver is doing.

GPS is now available for the MXL and looks to be a very valuable tool with lots of benefits. I am very excited about the GPS sensor as it opens up many new ways to look at the data.

We are just finishing our install of a MXL Pista, AiM GPS, and DaVid video system in our Mazda MX-5 Cup car that we will run in Houston on April 21st for the first time.

I am the official AiM trainer here in North America and most of my training is with the software. I also find that most folks do not know how powerful the Race Studio2 software is. The AiM hardware is very good but as some others have mentioned, the software is where you spend most of your time after getting the system up and running.

We work very hard to make sure not only our customers are pleased with their AiM purchase but have helped many others use their equipment to go faster and enjoy their racing even more!

Contact me and I would be glad to answer any questions you have on hardware and on your install. On our website we have lots of images showing how to install the systems and various sensors.

Knowledge = Speed!

Roger Caddell
Victory Lane Data

924RACR

Thanks!

Yes, I've done just what George did for speed sensor install with my AIM (no ABS! LOL) but with the added detail that I put the magnet not directly on the CV, but on one of the plate washers for the CV. This way I won't lose my speed signal if I have to swap a driveshaft at the track.

Regarding warning lights and steering angle; I have a pretty simple steer angle setup on my car; I use a string pot wrapped around the steering shaft. Clamping a pulley on there would provide higher resolution, but it's not bad as-is (steering shaft is about 1" OD). The string pot is mounted to the back of the plate which my MyChron3 display is mounted to, on top of my dash bar (which sits just above the steering column). As noted, it's fairly easy to calibrate using the user-defined sensor.

I'll put my vote behind what Roger says - the AIM RaceStudio software is top-quality. I work with data acq. in the day job (for vehicle dynamics, not racing), and the AIM SW is IMO right up there at the same level as our professional-level product (in-house Bosch SW). I often find myself trying to use keyboard shortcuts from our SW in the AIM SW (I do wish they'd add more in the AIM SW)!

For setting up warning lights; I actually don't usually run sensors into my AIM system, as I'm so limited in channels (only have 4), and I like to focus on driver development and vehicle dynamics. I'm usually logging at least long. accel, yaw rate, and steering input (not so interested in by brake input or throttle - I can threshold brake just find, and with maybe 100hp at the wheels most throttle applies progress go to WOT very quickly!). I'm trying to keep the last channel open for O2 when I get it hooked up.

So what I have done instead is splice into the stock oil pressure warning light circuit; I've added a red trailer clearance light (also mounted on my dash) as my very cheap ($1.50) Mega Low Oil Pressure light:

BrianKeithSmith

Caddell :

So I can feed any voltage (say 0-5v) into the AIM and program it to translate the voltage to a value?

In other word, if I know that 1.1v=xyz then I can set up a table in AIM and it will pick the closest value, showing me the xyz translation? Does it have that sort of functionality?

Thanks,

Brian

924RACR

Heck yeah! Or non-linear curves, etc. We set up a mapping for the stock oil pressure sender (VDO) which is decidedly parabolic.

BrianKeithSmith

Thanks - just wanted to make sure. I thought you could, just wanted to confirm (its been a year since I read the AIM MXL PRO manual).

But the xyz translated value can appear on the dash - correct? Not just on the laptop after reviewing the data? thanks

Brian