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Roland@pcmtec

HOWTO: Traction Control

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From the factory the Ford Falcon utilises a fairly aggressive throttle cut traction control. This is great for when your grandparents are driving in the rain with standard power. With 300rwkw+ this becomes quite useless and most people turn it off as it allows lots of wheel spin, then kicks in shutting the throttle completely which doesn't make for a predictable or fast car.

What is not commonly known is the standard traction control system isn't just a throttle cut, it uses enleanment (or enrichment if you modify it), spark retard and throttle cut.

For a performance application we can set up the standard system to simply utilise an aggressive spark retard only. This is very fast acting meaning traction loss is caught quickly, and with the throttle remaining 100% open, you do not lose boost. When coupled with boost by gear and flatshifting, this can mean putting 400rwkw to the ground with street tyres and 100% throttle is possible. It is an absolute must for a fast car.

To enable an aggressive spark retard only style traction control system, we will use a lot of the tables discussed in the launch control thread which can be found here. https://forum.pcmtec.com/index.php?/topic/104-howto-bf-manual-launch-control-flat-shifting-and-torque-requesters explained/

There are two guides here, a detail one which describes what each table does and why you modify it. At the end of the thread there is a monkey procedure if you just want to get it happening asap.

First we must disable the throttle cut on traction control. We do this by modifying auF0265 and setting "traction control" to 2000. This means the PCM cannot request less than 2000 ft*lb of torque during a traction control event. Eg it is disabled.

image.png.6b5b332103c8e82429db3a3f10a21900.png

Secondly we completely disable the ETC cut on traction control by setting the RPM enable setpoint ( auF0264 ) to 10,000 rpm. Technically either of these two settings would do, but to make it clear we disable both.

image.png.de802324ea1a99b3c7d839e4ff667e2f.png

On FGs there is another function auF11982 "Min torque ratio that can be achieve via spark retard to prevent backfires". Set all the torque ratios above 100°F to 0. Otherwise spark retard will be clipped at 0.3 or higher.

image.png.5cccc6c82ecaedeeed2fe9dbaceff672.png

Next there are two options, run enleanment during spark retard, or run commanded lambda. From the factory the vehicle will command 1.05 lambda. If you wish you can change this to cause an enrichment instead (safer) by setting auF1479 to something very rich like 0.5

This will mean the vehicle runs 0.5 lambda during a traction control event further reducing power.

image.png.b83760ed2bf0bf08644c5275c6985794.png

Or we can disable enleanment/enrichment during traction control entirely by modifying auF0261 and changing the traction control row to 0. This means enleanment/enrichment cannot be used during traction control. In this scenario the vehicle will run the commanded lambda instead.

image.png.8b4bf564d20b65e4ecb527be8c53fa62.png

Finally we set the minimum requested torque ratio for spark control auF0262. This controls how aggressive the spark retard will be. Setting it to 0 means the PCM can request 0 ft*lb of torque during a traction control event. This means the PCM will use the maximum spark retard possible which will most likely hit the factory spark minimum clip of -15 degrees.

Setting it this low can be too aggressive , personally in a manual vehicle I found a setting of 0.25 to be perfect as it let the vehicle maintain a very small amount of wheel spin.

image.png.105a792cbac3ca6562fefdaf0b2eaf19.png

Next we can modify the spark retard transfer function auF2233 (BF only). By setting the very minimum settings to -70 degrees, this means the PCM will very quickly hit the minimum clip. This will affect how fast the PCM reacts to the traction control event, think of it like adjusting the proportional gain. NOTE this table is used for ALL torque based spark retard requestors. If you have an automatic vehicle and you set anything above 0.5 (the default minimum torque ratio during a gearshift) to a lower number you would also affect the minimum spark commanded during a gear shift, this could make your shifts laggy and may be completely unnecessary, for this reason it is only recommended to adjust the 0 and 0.25 cells.

image.png.69158f87c1aabdb556d307491ad8b1c9.png

Finally auF16586 "Spark Min Clip" can be adjusted below the factory setting of -15 degrees. Note that going as low as -25 will induce backfires and high EGTs, only do this if you are sure your vehicle can handle the high exhaust temperatures. Sitting at -25 degrees timing for an extended period of time can burn valves very quickly and also destroy catalytic converters.

image.png.eaad9e8df6c946539ce52a3b66956169.png

 

Monkey guide:

Set auF0265 traction control row to 2000

Set auF0264 traction control row to 10000

Set auF1479 to 0.8 lambda (for safety)

Set auF0262 traction control row to 0 to 0.25 depending on how aggressive you want it. 0 is more aggressive.

Set auF11982 (FG Only) to 0 for all temperatures above 100°F

 

FG UPDATE

The FG uses a much more complicated 3D model instead of auF2233. In the FG the spark delta commanded is calculated using the following equation which is derived from what I imagine is an auto generated mathematical model:

Torque_ratio_commanded = 0.8 (eg we are asking for a 20% reduction in torque via spark retard)

K = auF1256(rpm,load)

K = -0.00032  (4500 rpm and 1.7 load in HAER1UB)
Torque_ratio_commanded = 0.8;
Spark_Delta = -Math.Sqrt(-(4 * K * (1 - Torque_ratio_commanded))) / (2 * K);

Spark_Delta = 25 degrees

Knowing this you can see that if you want more torque reduction, you need to reduce K

Eg a value of K = - 0.00016 would result in 35 degrees of spark retard. A value of K = -0.00064  = 17 degrees of spark retard.

So if we wanted to achieve the same outcome in an FG we would multiply the spark retard table on full load by say -0.5

Here is the original auF1256 table in an FG

image.png.b3fb7ab2ec27b76308f6166190ce984a.png

Here is the new table with approximately 25% more spark retard (will request approximately -35 degrees of spark retard instead of -25 degrees)

image.png.9ab460fcb35d6bc68bce3f0844d9cfad.png

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1 hour ago, Roland@pcmtec said:

On FGs there is another function auF11982 "Min torque ratio that can be achieve via spark retard to prevent backfires". Set all the torque ratios above 100°F to 0. Otherwise spark retard will be clipped at 0.3 or higher.

image.png.5cccc6c82ecaedeeed2fe9dbaceff672.png

 

What about the value at 100F is it 0.8 or zero? Thanks

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1 hour ago, Loki said:

What about the value at 100F is it 0.8 or zero? Thanks

Up to you. At lower than 100 f coolant temp do you want full spark retard to occur? 

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Someone PMd a question which I'm posting the reply to here as it gives a good example.

Quote

Hi Roland,

Been following your how to do topics, great read. Very quickly, trying to get my head around the values in both auf0262 and auf0261. Can you explain the torque ratio values i.e. a setting of 0 compared to a setting of 1.

5 minutes ago, Roland@pcmtec said:

auf0262 is the spark torque ratio lower limit. It means the PCM cannot command less than x% torque reduction via spark retard.

Eg if you have 0.8 in the traction control column and the ABS module requests 200 ft * lb of torque to control traction and the engine is making 400 ft * lb of torque the commanded torque reduction ratio will be  200 / 400 = 0.5

as 0.8 is higher than 0.5, the PCM creates a lower limit at 0.8 and requests a reduction of 20% torque via spark retard. It then looks up the torque to spark delta table. In this table 20% reductiuon is approximately a spark retard of -20 degrees.

So the PCM will subtract 20 degrees off the currently commanded spark value to reduce torque. Knowing this a value of 1.0 would cause no spark retard to occur and instead torque reduction would be done via other sources (fuel injector cut, ETC shut or enleanment). A value of 0.0 would allow -70 degrees spark retard to occur.

image.png.e004be5d7bc7fc1d5effd2361fa0f8bb.png

auF0261 is the same as auf0262 except for all other non spark retard related torque reductions. Eg enleanment, throttle shut and injector cut out.

The auf0262 description is sort of backwards. A higher value means more torque reduction (but less spark retard specifically) as it results in "other methods" taking over, these can shut the throttle causing 0 torque. Spark retard can only make small reductions in torque, eg maybe 20-50% maximum before you hit the spark min clip.

 

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Yes not all the parameters are available in professional as some of these are listed as "development parameters" which we did not previously know what they did. You can however get the same results by just increasing the amount of spark retard at approximately 0.2 and above torque ratio.

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Pardon the noob, but my FG Mk1 has the “spark min clip” identified as auF16586. Factory setting is -11. Any big issues with setting this to -20? Everything is factory FG Mk1 GS.

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25 minutes ago, Gonads said:

Pardon the noob, but my FG Mk1 has the “spark min clip” identified as auF16586. Factory setting is -11. Any big issues with setting this to -20? Everything is factory FG Mk1 GS.

 

On 3/9/2019 at 5:32 PM, Roland@pcmtec said:

Note that going as low as -25 will induce backfires and high EGTs, only do this if you are sure your vehicle can handle the high exhaust temperatures. Sitting at -25 degrees timing for an extended period of time can burn valves very quickly and also destroy catalytic converters.

 

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Yeah thanks Roland. I actually did read your post and my question was based around the fact that my factory setting was 11, not 15. Once again, pardon the noob question. I’ll put on my dunce hat and sit in the corner now :).

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Putting on Dunce hat again in advance.....I can't find auF2233 in my ROM. I seriously looked until asking potentially dumb question was my only option.

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I'm not sure what causes Ford to change the factory settings there. Maybe different exhaust and turbo mean different temperature limits.

Regarding auF2233 Are you running the pro version of the software? Which strategy or catch code is your vehicle?

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2 hours ago, Roland@pcmtec said:

I'm not sure what causes Ford to change the factory settings there. Maybe different exhaust and turbo mean different temperature limits.

Regarding auF2233 Are you running the pro version of the software? Which strategy or catch code is your vehicle?

Mine is FGX G6E turbo and I can not find auF2233 in my strategy!

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4 hours ago, Roland@pcmtec said:

I'm not sure what causes Ford to change the factory settings there. Maybe different exhaust and turbo mean different temperature limits.

Regarding auF2233 Are you running the pro version of the software? Which strategy or catch code is your vehicle?

Hi Roland. I’m running pro version and the car is Mk1 GS Miami catch code HAFFAE3.

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2 hours ago, Loki said:

Mine is FGX G6E turbo and I can not find auF2233 in my strategy!

Ok so the BF (what this guide was originally written for and tested on) has a simple auF2233 table which is a lookup of torque reduction ratio and spark delta to command.

The FG uses a much more complicated 3D model. In the FG the spark delta commanded is calculated using the following equation which is derived from what I imagine is an auto generated mathematical model:

Torque_ratio_commanded = 0.8 (eg we are asking for a 20% reduction in torque via spark retard)

K = auF1256(rpm,load)

K = -0.00032  (4500 rpm and 1.7 load in HAER1UB)
Torque_ratio_commanded = 0.8;
Spark_Delta = -Math.Sqrt(-(4 * K * (1 - Torque_ratio_commanded))) / (2 * K);

Spark_Delta = 25 degrees

Knowing this you can see that if you want more torque reduction, you need to reduce K

Eg a value of K = - 0.00016 would result in 35 degrees of spark retard. A value of K = -0.00064  = 17 degrees of spark retard.

So if we wanted to achieve the same outcome in an FG we would multiply the spark retard table on full load by say -0.5

Here is the original auF1256 table in an FG

image.png.b3fb7ab2ec27b76308f6166190ce984a.png

Here is the new table with approximately 25% more spark retard

image.png.defede9aa2d01757c2858c397eabf664.png

This actually gives us a lot more control over the spark retard for traction control in some regards, if you wanted aggressive traction control to only occur at certain loads and rev ranges, you can now achieve this. In the BF this would not be possible.

Remember this is used for all torque reduction events, so this will affect your transmission shifts etc. The BF version would not affect your transmission shifts as you could only modify the low torque ratio settings.

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On 3/12/2019 at 8:08 AM, Roland@pcmtec said:

Yes not all the parameters are available in professional as some of these are listed as "development parameters" which we did not previously know what they did. You can however get the same results by just increasing the amount of spark retard at approximately 0.2 and above torque ratio.

what table or scalar are you referring to in regards to this?

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On 3/14/2019 at 12:50 PM, Roland@pcmtec said:

Ok so the BF (what this guide was originally written for and tested on) has a simple auF2233 table which is a lookup of torque reduction ratio and spark delta to command.

The FG uses a much more complicated 3D model. In the FG the spark delta commanded is calculated using the following equation which is derived from what I imagine is an auto generated mathematical model:

Torque_ratio_commanded = 0.8 (eg we are asking for a 20% reduction in torque via spark retard)

K = auF1256(rpm,load)

K = -0.00032  (4500 rpm and 1.7 load in HAER1UB)
Torque_ratio_commanded = 0.8;
Spark_Delta = -Math.Sqrt(-(4 * K * (1 - Torque_ratio_commanded))) / (2 * K);

Spark_Delta = 25 degrees

Knowing this you can see that if you want more torque reduction, you need to reduce K

Eg a value of K = - 0.00016 would result in 35 degrees of spark retard. A value of K = -0.00064  = 17 degrees of spark retard.

So if we wanted to achieve the same outcome in an FG we would multiply the spark retard table on full load by say -0.5

Here is the original auF1256 table in an FG

image.png.b3fb7ab2ec27b76308f6166190ce984a.png

Here is the new table with approximately 25% more spark retard

image.png.defede9aa2d01757c2858c397eabf664.png

This actually gives us a lot more control over the spark retard for traction control in some regards, if you wanted aggressive traction control to only occur at certain loads and rev ranges, you can now achieve this. In the BF this would not be possible.

Remember this is used for all torque reduction events, so this will affect your transmission shifts etc. The BF version would not affect your transmission shifts as you could only modify the low torque ratio settings.

Hi Roland, my tables only go up to .95 load. strategy HAFDDB6.

How do I go about torque reduction under full load?

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37 minutes ago, Zaz3ry said:

Hi Roland, my tables only go up to .95 load. strategy HAFDDB6.

How do I go about torque reduction under full load?

You must have an NA vehicle then, or someone has enabled turbo logic on an NA calibration. The table will simple peg at 0.95 so you can still modify it, or you could use the reinterpolate wizard as discussed here to change the axis range.

 

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Further testing required but to disable traction control in a MK 2 FG:

Set auF0410 to Disable  ETC Traction Contol :

image.thumb.png.fca199fd94ab11d50133090cc01505e4.png

And set auF2495 to 0:

image.thumb.png.b90fa36bbe6b3b624eb4f50431c8d1fc.png

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