update?

Hi Mdessouki,

Yes we were able to use the ABS wheel speed sensors for launch and traction control, without the ABS system getting upset. However, we found out that aside from the interface board, we needed to add transformers to each wheel speed sensor to couple the signal correctly. I've attached a picture and you'll see how clunky the interface becomes. We definitely need to make something cleaner.

Thanks.

Thanks for the update. My understanding is that if ABS is disabled, one could use a fairly basic circuit to convert the sinusoidal VR output into a squarewave which can be interpreted by the Adaptronic. Is this correct?

Would something like this suffice?
Dual VR Conditioner Board V2.1

Or maybe a GM HEI?
Attachment 547064

I'm not sure I understand the purpose of the transformers when retaining ABS function. Are they being used to amplify the VR output or is it for something else?

Thanks for all the hard work :bigthumb:

Hi mate,

The transformers used are actually just 1:1, but we figured we needed those so we don't mess up with the signal phase of the ABS sensors when we splice to them directly and that's the one that upsets the factory ABS box.

In theory, the Select ECUs should be able to read the ABS sensors directly. But I wanted to make sure first hand so I wanted to try it on an actual RX7. Actually I got to try this on my car's (non-RX7) ABS sensor last week, and it did read the speed, but wasn't reading well at low speeds. So probably the signal really needs to be amplified / conditioned.

I'll give an update soon.

I wasn't aware the select ECU could read the VR signal directly. Why not use a signal conditioner? The MAX9924-9927 was made specifically for this and is pretty much ideal. It has 2 VR signal conditioners on one IC, 100kΩ input resistance, and adaptive peak threshold which will compensate for the lower pulse voltage/noise at low speeds. They are also quite cheap, only about $5 USD a piece :icon_tup: MAX9927AEE+ Maxim Integrated | Mouser

MAX9924-MAX9927 Datasheet

Thanks for sharing mate! Definitely looks like it should work :icon_tup:

Our ABS interface board will do the same, and 1 board has 4 channels/inputs already. I was just testing how well the Select ECUs will read the ABS sensors without the interface board.

Cheers.

Any update mark?

Interested as well.

Hi guys,

I'm very sorry for the delay, I only had the chance to test the ABS sensors wired directly (no interface board) to the Adaptronic the end of last month, and it didn't work well (i.e. didn't read well at low speeds).

So now I'll post the wiring / schematic we currently have on the car, but before I do that, it is important that I say that splicing into the ABS wiring is at your own risk. Don't try to do this, if you're not really comfortable with wiring stuff. Also, we only recommend this mod done on race cars and not on road legal cars.

But yeah, here they are:

Figure 1 is what we did to splice into the factory ABS sensors, without upsetting the ABS control unit. We've used the transformers in between the sensors and the Adaptronic ABS interface board to couple the signal instead of wiring directly. Wiring them directly messes up with the signal's phase and the ABS control unit doesn't like it. The schematic of the interface board is also shown in case you want to make one yourself.

Figure 2 is a case where you have the ABS sensors available, but don't have the ABS control unit or is not working anymore. I.e. so we don't have to worry about it getting upset and throwing a light.

The last picture shows the traction control settings that I used when I tried it on my mate's car.

There is also an option to use a potentiometer to adjust the target wheel slip, so you don't need a laptop when you want to change the sensitivity of the system. However the POT needs to be wired into the ECU's spare / external 0-5v analogue input, so you only have this option if that input pin is free.

If you have questions, please let me know. Post it here or email me at tech@adaptronic.com.au

Thank you.

How do you think the low speed performance will be with the module on a street driven vehicle? Debating abs delete.

Hi Monkman33,

I'm not sure I get what you're asking, but we definitely don't recommend deleting / disabling the ABS system. The wiring and module shown (with the transformers), if done correctly, will not affect the ABS system. The ECU only uses the wheel speed sensors to detect loss of traction while trying to accelerate, and this is where the ECU will be cutting power.

Please let me know if this doesn't answer the question.

Thanks.

Mark,

Sorry i was vague. You said it didn't read the signal well at low speeds with the sensors directly wired to the adaptronic. Is that because the abs was effectively removed? So i am guessing the adaptronic picks up the signal better using the module with all other abs equipment in place?

I'm only considering removing abs because of autocrossing.

Please correct me if I'm wrong.

In the configuration mark posted the wheel speed sensors are being 'tapped' into before the ABS computer using a transformer in order to keep the signals isolated. The transformer is basically 'listening' to the output of the speed sensor, not interfering with it. The poor performance at low speeds is a due to an unconditioned signal. Without proper signal conditioning a VR sensor will only give a usable signal at medium to high speed. Several different sources sell pre-made VR conditioners that could be used. IMHO don't try this in its current state, wait for Mark to release his interface board.

Hi all, was interested in this and I tried to do some more digging on the adaptronic forum, majority of the info on this thread and adaptronic forum is the same. Traction Control and Pulses per rev

Frank said that the board is for sale via adaptronic. I am not quite ready yet myself, but FYI to everyone.
I am interested in seeing the board itself, and perhaps installation instructions for when I am ready/get more time.

Hi guys,

Bowlcutsaresweet is correct in his explanation. Thanks mate!

Silentblu, yes the interface board is actually an Adaptronic saleable product (picture attached) and we sell them for $60+GST if you're in AUS (ask Turblown if you're in US). It's actually a cool board because it has 4 x ABS wheel speed interface, an ignition output expander circuit, a stepper motor driver circuit, and a few more bits. I've posted the 4 x ABS wheel speed interface circuit if one's only interested in that and would want to make one himself.

However, the thing that we didn't expect before I started the test (last year) is that the RX7 ABS system would be unhappy if we tap to it directly. So our solution was to add transformers to "mirror" the signal and this worked, however that adds to the cost now.

So really the best thing for us to do is to make a new interface with the transformers now like bowlcutsaresweet said. But then again we would only make a new product if there's enough demand for it, so I've posted the schematic if anyone wants to try it DIY.

Cheers.
Mark

Frank mentioned it on the adaptronic forum. How would this interface with the adaptronic? Will there be wiring included as well?

For the ignition expander and stepper motor driver, would that mean there would be an additional PWM aux out, meaning I could do the following:

With what I have right now: 440D
Aux 1 PWM - Direct Fire/Ignition 4
Aux 2 PWM - IAC/Idle Control
Aux 3 PWM - Wastegate/Boost Control
Aux X (new interface board) PWM - Auxiliary Injection

With the additional ignition output I would finally be able to do the triple spark plug per rotor!! :lol: pipe dream :crackup:

I would be interested in a premade one. I already have the stepper motor expander to run the omp from less outputs.

Totally off the wall question here, would it be possible to replace the factory sensors with hall sensors on the abs rings?

Mark, what transformers are you using to couple the board? Any links or pics?

Cheers
Glenn

See the beginning of the thread. But I believe Chris answers it pretty well at post #10

BTW how does your stepper motor expander work/interface? Any add'l info?
I need one additional PWM output.

Not sure yet. Haven't installed it. I'm not even sure how to wire it up yet. It is the push pull driver on turbosource.

Silentblu,

- This board won't give you aditional PWM aux outputs, sorry.
- The stepper motor driver circuit allows you to control a stepper motor using only 2 x aux outputs from the ECU, instead of 4, thus saving aux outputs.
- The ignition expander is also meant to fire sequential-six only with the current firmware (really intended to fire the Toyota 1JZ/2JZ non-VVT as sequential).

Monkman33, I think most Hall sensors would be too big for the ABS rings.

Glenn, we used these - LM-NP-1001-B1L Bourns | Mouser

Cheers.

The most common use for the stepper motor driver circuit on a rotary engine would be for the OMP (RX7 S5-S8) and if you're using an e420d or an e440d (so you don't consume 4x aux outputs if you're using the OMP). If you have a plug and play Select, it's already built-in.

This video explains how to use it for a stepper motor idle valve -

Thanks Mark,

I figured the transformers were something like that :) Will put a board together :)

So where did we land on this? I don't follow most the jargon after post #27... Given there were 30+ people that signed up for the $1,000+ racelogic traction control group buy I'm sure you could drum the some interest in a simplified product.

Also, I'm not opposed to adding additional sensors if required.

Any update/ any idea how difficult it will be to set up traction control on the new modular unit?