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BNR34 AWD traction control (atesa + ABS sensors), who has done it ?


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Hi,

I'm currently benchmarking ECUs for my r34 gtr,
I would really like to have traction control using the ABS sensors and the transfer case.
So far I found syvecs and powertune (motec) which seem to have such feature.
However I have some questions regarding the traction control feature.

However except a r33 gtr rwd demo car from powertune, I couldn't find anyone who has done it ?

Best regards

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I have implemented traction control with a RWD R34 GTT and using a Racelogic system.

They generally work the same, they measure front wheel speed and rear wheel speed, and if there is a difference between them, then they do "Something"


"Something" is user definable in all of the ECUs that manage this. This is all they really do, they can cut timing, ignition, fuel, boost, etc (pending on system) in order for the difference in wheel speeds to catch up again.

TBF, the AWD system in a GTR really is just a mechanical traction control system to begin with...

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On 3/23/2022 at 6:33 AM, Kinkstaah said:

"Something" is user definable in all of the ECUs that manage this. This is all they really do, they can cut timing, ignition, fuel, boost, etc (pending on system) in order for the difference in wheel speeds to catch up again.

Modern e-throttle FTW.

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You can't use the factory ABS sensors to do so, as they don't produce a square wave.

A potential solution is to use the VSS input and a GPS sensor and then calculate slip percentage between GPS speed vs. VSS.

Halaltech does this too, if you're after a cheaper-ish solution.

I'm planning on setting up traction on my car too, however will mount a hall effect sensor to one of the front un-driven wheels (I have a GTS-t) and point it at the wheel studs.

You can build tables to do things like:

  • slip percentage vs. boost trim
  • slip percentage vs. timing retard
  • slip percentage vs. throttle trim (if you're using DBW)

The world is your oyster really, here's one I quickly mocked up in the Haltech

image.thumb.png.bd1079f82b0c7bdc9b04847c1f266cf2.png

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On 24/03/2022 at 8:27 AM, Kinkstaah said:

..... I use the factory ABS/wheel speed sensors just fine?

Perhaps the Racelogic system is different? There is another system which is standalone (www.raceTCS.com) which is another option.

It is different, as in there are 2 versions. One for square wave speed sensor version and the ABS sine wave version which splices into the ABS sensors.

https://www.vboxmotorsport.com/wiki/TractionControl

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On 24/03/2022 at 10:16 AM, Dose Pipe Sutututu said:

You'll also find that lowering the resolution, i.e. less teeth to count means you can calculate higher wheels speeds and have less errors.

With the Nissan ABS ring there are way too many teeth to count, kind of like how they failed with their CAS design LOL.

46 tooth to be exact. Would it really be a problem with the factory reluctor ABS sensors, being that you are effectively reading a frequency change ?

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https://www.full-race.com/ets-pro-nissan-skyline-gt-r-center-differential-attesa-torque-split-controller-for-r32-r33-r34

If you want a new ATTESA controller this is what you're looking for. If you want more after that then you're looking at some kind of stability control/traction control which requires DBW to execute properly and I believe is beyond what your average Haltech is capable of. Most ECUs out there are only going to do something like cut throttle if too much slip is detected. Nothing near what a modern stability control system is capable of. Maybe a Life Racing or similarly motorsport oriented unit can be on par with modern VSC/TC.

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On 24/03/2022 at 11:54 AM, BK said:

46 tooth to be exact. Would it really be a problem with the factory reluctor ABS sensors, being that you are effectively reading a frequency change ?

Theoretically no, however I've seen on Guild of EFI many suggesting to grind off teeth OR just count the back of the wheel studs where possible, i.e. 5 events per wheel revolution, or 67 per sec if you're doing about 100km/h on a 255/40/18 tyre (used a tyre calculator online, could be wrong lol).

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On 24/03/2022 at 10:59 AM, joshuaho96 said:

https://www.full-race.com/ets-pro-nissan-skyline-gt-r-center-differential-attesa-torque-split-controller-for-r32-r33-r34

If you want a new ATTESA controller this is what you're looking for. If you want more after that then you're looking at some kind of stability control/traction control which requires DBW to execute properly and I believe is beyond what your average Haltech is capable of

You did not read this from Dose Pipe did you, as the Elite is quite capable

On 23/03/2022 at 9:12 AM, Dose Pipe Sutututu said:

You can build tables to do things like:

  • slip percentage vs. boost trim
  • slip percentage vs. timing retard
  • slip percentage vs. throttle trim (if you're using DBW)

The world is your oyster really, here's one I quickly mocked up in the Haltech

image.thumb.png.bd1079f82b0c7bdc9b04847c1f266cf2.png

 

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On 3/23/2022 at 7:28 PM, BK said:

You did not read this from Dose Pipe did you, as the Elite is quite capable

 

It's not bad but it's hard to say what OP is looking for. If they're looking for something on par with MDM DSC in BMW M cars or VDR R mode in the R35 GTR you need so much more than just a throttle cut vs slip ratio. I don't even know if it makes sense to bother with something that complicated. 

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On 3/23/2022 at 9:22 PM, Dose Pipe Sutututu said:

Throttle cut is so 10 years ago, you missed the part where I actually demonstrated simple torque reduction based on wheel slip percentage.

 

That's still really far off from something that estimates driver intent based on steering angle/lateral g and possibly also activates the brakes. Not dumping on the Haltech, it's good but I'm not sure that any standalone ECU in general is really going to support some crazy complicated thing like what you see in a current year M3.

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On 24/3/2022 at 3:34 PM, joshuaho96 said:

That's still really far off from something that estimates driver intent based on steering angle/lateral g and possibly also activates the brakes. Not dumping on the Haltech, it's good but I'm not sure that any standalone ECU in general is really going to support some crazy complicated thing like what you see in a current year M3.

That is stability control and not traction control. They’re related but not the same 

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On 3/24/2022 at 11:46 AM, Dose Pipe Sutututu said:

You'll also find that lowering the resolution, i.e. less teeth to count means you can calculate higher wheels speeds and have less errors.

With the Nissan ABS ring there are way too many teeth to count, kind of like how they failed with their CAS design LOL.

I guarantee the nissan wheel speed sensors work fine from 4km to 250kmh on 265/35/18 tyres. It isn't too many to pick up and absolutely works entirely fine.

The system I use (and the RaceTCS one) cuts fuel. It is more than enough to lower the car's speed and using anything else is just fussing around for no reason. It does work better in V8 land though, due to the linear power delivery than it did when I was I6T.

It's pretty much a set and forget system. I wouldn't be bothering with anything other than fuel cut, using throttle sounds good, lowering boost sounds good, changing ignition timing sounds good but in the real world I just can only imagine scenarios where it doesn't cut enough to cause the slip to take effect.

In my scenario the time that traction is cut is tiny fractions of a second, it loses and regains grip much quicker than I would expect any boost controller or throttle blade to react. You do not notice the actual cuts when they happen - The car just feels like it has grip on the ground, in 1st at WOT.

Then you turn it off to test and you're amazed. This is the way.

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Not bagging on your system, however on the likes of Haltech or similar you have much more control over what you want to do and how aggressive.

You can build traction levels/tables and assign them to a keypad or rotary switch too.

You essentially can layer:

  • Fuel cut
  • Ignition reduction 
  • Cylinder cuts
  • reduction in boost DC
  • reduction in throttle position
  • RPM limits

So depending on the wheel slip you could layer on more and more, this control is far superior to a system that just cuts fuel.

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On 3/24/2022 at 5:30 PM, Dose Pipe Sutututu said:

Not bagging on your system, however on the likes of Haltech or similar you have much more control over what you want to do and how aggressive.

You can build traction levels/tables and assign them to a keypad or rotary switch too.

You essentially can layer:

  • Fuel cut
  • Ignition reduction 
  • Cylinder cuts
  • reduction in boost DC
  • reduction in throttle position
  • RPM limits

So depending on the wheel slip you could layer on more and more, this control is far superior to a system that just cuts fuel.

I'm not saying merely fuel cut is somehow superior, I was really just saying it is no issue with regards to the factory ABS sensors being unsuable as a metric for wheel speed. It absolutely does work, and doesn't have errors and doesn't need less teeth to work or what have you.

More control is more better, I agree - But it's just one of those things where minimal config gives max results. It is in effect a cylinder cut system, but even on a Haltech I can't see anyone attempting to layer them over the top, because running on 5cyl instead of 6 is a very effective cut (or 7/8), and at 5000rpm this is an effect that is 'polling' very, very frequently, it feels pretty damn seamless. More control is more better, but sometimes it pays to not overcomplicate things for no real benefit, that's all..

I do have a rotary switch with mine (but even so, I usually leave it at 10%), and you can configure how aggressive the cylinder cuts with TC in stages, i.e 

At X% slip, use this cut pattern, at Y% slip use this cut pattern, at Z% slip use this cut pattern, etc. The benefit of having a Haltech is at MASSIVE slip scenarios, if you have a fuel controller or such your car will actually know about it, and not think the car is just running mysteriously lean and run into limp mode/engine protection. Or at least you'd hope it would know about it!

If you get such a system, just experiment with cyl cut and you will likely find thats all you need 😛

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