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HOWTO: BF Manual Launch Control / Flat shifting and Torque Requester's explained

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Falcon Torque Control Explained.

IMPORTANT: Flat shifting and launch control can destroy axles, diff bushes and tailshafts if they are standard. Make sure you are ok with the possibility of replacing these. It is recommended to install a diff hat at a minimum and ensure you have no axle tramp.

The Falcon PCM works on torque. Normally under normal conditions eg no cruise control, no over temp, no traction control, no rpm limiting it will source torque from "driver demand", eg whatever your foot says it will do.

Now under various conditions it will move out of driver demand and request a different torque source. The various torque sources can be seen in the torque requestors below.

image.png.7c1d85d9fee7c413bbcd3ccb0d433601.png

Now that we know there are various torque sources, how is the torque actually controlled?

The torque is controlled via the following mechanisms.

Spark Retard, AFR Enleanment, Cylinder Fuel Cut, ETC (Throttle cut) and full injector cutout.

Firstly it calculates a desired torque ratio which will be less or more than is currently being produced.

Depending on what the torque source is this is calculated differently. Eg in rev limiting it uses Desired_RPM / Actual_RPM * Engine_Friction

Eg if you are at 6200 rpm, but the rev limit is at 6000 rpm. Assuming the engine friction is a linear relationship you would see:

6000/6200 * K = 0.96

Eg the PCM would request 96% of the torque that is currently being produce. Eg it would ask the PCM to produce 4% less torque than it is currently producing.

Now how does it reduce the torque?

The PCM uses the following calculation to determine how much of the above methods are utilised.

First it tries to reduce the torque using spark retard.

Eg if the requested torque is 0.6, eg a 40% reduction in torque it will compare the 0.8 to the values in auF0262 (Spark Torque Ratio Limit)

image.png.c4d9a038b81bdaf35f8ff2ebad82f8dd.png

In the example of rev limit it will compare the 0.6 to the value in auF0262 (which is 0.8)

The PCM will then take the maximum of the two numbers and only provide 0.8 torque reduction via spark (eg it will limit spark retard to only a 20% reduction whilst in engine speed limiting).

The PCM will then also compare this value to auF11982 "Min torque ratio that can be achieve via spark retard to prevent backfires"

image.png.5cccc6c82ecaedeeed2fe9dbaceff672.png

As you can see when the coolant temp is lower than 100°F it will limit the spark retard even further to a value between 1->0.8 eg less than 20% when cold.

There is then a further absolute minimum number auF12516 which is typically 0.2 eg 80% reduction, this will never be reached with the standard calibration numbers.

Knowing these tables exist if you wish to command a full 100% spark torque reduction you will need to change both auF12516 and auF11982 to b 0, eg a 100% torque reduction is possible

Now the PCM will decide if it requires other methods to reduce torque. It decides this via auF0261 "Torque ratio level above which spark only torque reductions occur".

image.png.838417c57a0863a2f042b1774069a68f.png  

Eg if we are limiting engine speed and the desired torque is above 0.8 then it will use spark only. If we are requesting 0.6 (eg 40% torque reduction) then the PCM will realise that spark alone will not be able to achieve this and move onto the next method of torque reduction.

Next the PCM will use enleanment.

Enleanment is next performed by making the engine run as lean as possible without a misfire. During torque reduction the value of auF1479 (1.05 lambda standard) will be used for commanded lambda. This means during torque reduction (eg traction control, or ZF gearshifts) the engine will be running lean, depending on the spark you have used in your lambda spark tables this may mean the engine starts knocking.

You can fairly safely change auF1479 to 0.7 or some other rich value for safety if you prefer.

Next the PCM will use cylinder fuel cut AND enleanment.

Fuel cut will be used to further reduce torque (sounds like a misfire and causes pops on gearchange in the ZF)

The cylinder fuel cut calculation is simply desired_torque_ratio * number_of_cylinders.

Eg if the PCM is commanding a 0.4 torque reduction (eg a reduction of 60%)

0.6 * 6 = 3.6 ~= 4

Eg 2 cylinders will be turned off.

Next the PCM will use the ETC (Electronic Throttle) to reduce torque. As the ETC is the slowest method to control torque it is used as a last resort.

During ETC control the PCM uses a PID controller to continue to reduce the throttle position to control to a given RPM point.

This means the throttle will move up and down continuously based upon torque error until it reaches steady state.

Now there is a final item called ETC Clip which clips the throttle at a minimum torque value.

To determine if the ETC will be clipped at a minimum torque level the PCM uses an RPM enable setpoint.

image.png.2c1a7d1bcc35459749623e6f5365832d.png

if (engine_rpm < auF0264 [torque_source]) ETC_Clip_Enabled = True;

In the example of traction control we can see that if the RPM is below 1100rpm it will enable ETC_Clip mode.

When ETC_Clip mode is enabled the PCM will limit the amount of torque the ETC can reduce the engine from producing to the value found in auF0265 "Amount of torque to clip"

image.png.f81cab6a08bab1b050c20452bdf19fab.png

Eg if the RPM is below 1100 rpm traction control will not be able to limit the torque below 40 lb *ft of torque.

In the FG falcons with launch control the ETC clip has a value of 550 in engine speed limiting. This means the ETC cannot ask for less than 550 lb * ft of torque. Eg the ETC will not close at all during engine speed limiting.

Finally in the FG falcons only there is a launch control enable flag. When launch control is enabled (speed less than 5mph and clutch pushed in) it uses an etc_clip enable rpm setpoint found in auF11985 which is set to 3800 rpm. It also changes the RPM limit to the value found in auF2035

So we can see from the above that in an FG manual falcon if the revs are below 3800 rpm the PCM will stop the ETC from being able to limit torque to control the rpm. This means only enleanment, cylinder fuel cut and spark retard will be used. In all other conditions the ETC will be enabled.

Now that we understand how all the different modes of torque reduction work (clear as mud?) we can see how we can enable launch control in a manual BF falcon.

 

To enable cylinder fuel cut based Launch control in a BF Manual enable the following parameters.

auF2035 Fuel cut RPM for launch. - This is your launch RPM, typically it is set at roughly 3500 rpm. If you raise it ensure you raise the rpm in auF0264

auF0264 ETC Torque Reduction RPM

Set Engine Speed Limiting to 3800 rpm (or your required launch rpm + ~300 rpm) This means if the rpm exceeds this setpoint the throttle will cut to ensure you don't overrev.

auF0265 ETC Clip Torque Requestor

Set Engine Speed Limiting to 2000 lb*ft. This will ensure that the ETC cannot be used to limit revs as the engine will never make 2000 lb*ft of torque.

auF0262 Spark Torque Ratio Limit

Set Engine Speed Limiting to 0.0 This will ensure the PCM can command 100% torque reduction via spark retard. Eg it can command the minimum spark of -15 degrees.

auF0261 This is the maximum ratio that will be used for all other torque cut sources

Leave Engine Speed Limiting at 0.8. If you set this lower you will get a spark retard only which will not hold the revs. If you set this to 1.0 you will never get spark retard. You can experiment here.

auF12516 "Minimum torque ratio below which torque reduction via spark are not possible."

Set this to 0, this means we can command 0% torque via spark retard.

auF1215 Sets minimum launch rpm for manual transmissions when set to 1.

Set this to 1, as this enables the launch mode functionality. Without this set launch control will never activate.

auF11982 "Min. torque ratio that can be achieved via spark retard during cyl. cutout. " Set this to 0 in the "Torque Ratio" column to ensure 100% spark torque reduction can be achieved.

auF2233 Transfer function which returns a spark retard from MBT as a function of desired torque

Set the top cells to -70, this means you will get the minimum spark retard clip value when in launch control. This is typically -15 degrees.

image.png.e004be5d7bc7fc1d5effd2361fa0f8bb.png

auF11078 "Source of Vehicle Speed Signal to activate Launch rpm limiting"

You may not need to change this however if you set it to 0 then all possible speed sources will have launch control enabled. Best to set it to 0 as a catch all.

Have fun!

EDIT:

UPDATE

We should be able to achieve flat shifting in the manual using the same logic. Simply wind out the minimum speed auF11836 from 10mph to 200 mph

image.png.2263d716eb1f533d605885df1c234262.png

This should cause a full fuel cut on gear shifts above 3500 rpm (or whatever your launch rpm is set to).

Edit:

The type of torque reduction performed is defined here:

image.png.20a011e75a263bdebfd1866a5848a5ab.png

1 = ETC (Throttle only)

2 = Spark retard, enleanment, injector cut and ETC

3/4 = Spark retard, enleanment injector cut only

4 may have been different in earlier models (BA) where they could run as lean as 1.2 lambda, due to NOx emissions this function is disabled effectively making mode 3 and 4 identical.

Edit 2:

For the FG the spark retard ratio is calculated differently. Please read this post for information.

 

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On 9/2/2018 at 7:45 PM, DarkHorse said:

 

1 hour ago, jagmotive said:

in the search bar auf12516, auf11982, auf2233 and auf11078 dont come up. any ideas?

What happens if you manually browse for those items? 

Which vehicle? 

Not all vehicles may have that logic in the PCM. 

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8 hours ago, jagmotive said:

they dont show up at all

bf turbo 07

strategy HACCKJ7.HEX

 

I just loaded that strategy and searched for "Minimum torque ratio" and found auf12516. It is found under Workshop/Professional Development Parameters then Development Scalars.

 I didn't look for the rest but searching for the name of the table etc should yield some results.

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I have a similar finding to jagomotive

I can find auf2233 but not auf12516, auf11982 or auf11078.

BF XR8 2006

Strategy HADCEP3.HEX

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37 minutes ago, FrogXA said:

I have a similar finding to jagomotive

I can find auf2233 but not auf12516, auf11982 or auf11078.

BF XR8 2006

Strategy HADCEP3.HEX

 

I just created that file, typed in auf12516 and it was in the same place as my post above.

Copy the scalar number and paste it into the search bar and it should come up. You will need to be in the workshop version as it isn't visible in the Enthusiast and Professional versions. Perhaps this is something that the developers can comment on further.

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1 hour ago, Puffwagon said:

 

I just created that file, typed in auf12516 and it was in the same place as my post above.

Copy the scalar number and paste it into the search bar and it should come up. You will need to be in the workshop version as it isn't visible in the Enthusiast and Professional versions. Perhaps this is something that the developers can comment on further.

Thanks Puff. That probably explains why they're not showing up then as I'm using the professional version not workshop.

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On 10/11/2018 at 7:11 PM, FrogXA said:

I have a similar finding to jagomotive

I can find auf2233 but not auf12516, auf11982 or auf11078.

BF XR8 2006

Strategy HADCEP3.HEX

You need workshop for those, but they aren't critical. You can still enable launch control, you just can't adjust the spark retard ratio.

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Thanks Roland. I'll give it a crack when I get a chance and see how I go. I assume my launch RPM etc. would need to be slightly lower given the greater low rpm boost and torque of my Kenne Bell supercharged v8?

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Just now, FrogXA said:

Thanks Roland. I'll give it a crack when I get a chance and see how I go. I assume my launch RPM etc. would need to be slightly lower given the greater low rpm boost and torque of my Kenne Bell supercharged v8?

Honestly any rpm will probably fry the tyres. I found you either got wheels pin or if you leave traction control enabled its not too bad. Will snap Axles as well. 

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Actually that's a good point about the axles. I might try this carefully and see how I go. Thanks for your advice.

Awesome software, by the way. Keep up the good work mate :)

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I've got the CAT600 bushes and a Herrod 2 piece 1350 uni tailshaft but have not done axles. No axle tramp but haven't really launched it hard so I'll see how I go.

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Hi I have a barra and th400 auto in a xf falcon with the pcm set to a manual ba f6.

iam trying to achieve a launch control off a button with no luck. It will rev to the preset launch rpm but won't rev parst it.

I have a earth to a button to pin b5 on the pcm but its not switching over to it normal rev limit am i missing a parameter to turn on / off.

Cheers 

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I have datalogged the clutch switch and with the ignition turned on it comes up with not depressed then 12 seconds later it changers to depressed with out touching the switch.

I have two manuals that say it is earth triggered and one that reads it is 12v to low volts?.

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1 hour ago, Carl said:

I have datalogged the clutch switch and with the ignition turned on it comes up with not depressed then 12 seconds later it changers to depressed with out touching the switch.

I have two manuals that say it is earth triggered and one that reads it is 12v to low volts?.

 

Screenshot_20190508-222721_File Viewer.jpg

Screenshot_20190508-200924_Gallery.jpg

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I’ve looked into doing something similar to this in the past as it was a question that was asked, however never had the opportunity/need to actually do it. 

 

From every wiring diagram I had looked at (mainly fg) the clutch switch was grounded.

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@Carl as per the drawing that you attached previously and the wiring diagram below, the clutch switch is wired to ground. When you depress the clutch pedal, the switch will close and complete the circuit to ground. 

How I'm assuming the input works is it's constantly measuring voltage (voltage is referenced to ground/negative), so if the clutch isn't depressed than the input should be 12v but when the clutch is depressed and it's switched to ground it should be 0v or pretty close to that as there is no/very little potentional difference between the two. 

394474537_Clutchswitvh.thumb.png.2fa95b6bfb0ab814543db4495ad2ff1d.png

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I am starting to think I need to set it up with a pullup resister in between. But not 100% sure.

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4 hours ago, Carl said:

I am starting to think I need to set it up with a pullup resister in between. But not 100% sure.

Are you running the auto or manual calibration? I would expect if it's using the auto calibration the actual state of the CES is ignored. If there was a switch to enable / disable the switch, I'd be looking under System Switches, but I cannot see anything in the FG/FG2 calibration (but it might be different on the BA calibration)

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8 minutes ago, Carl said:

Running a manual ba f6 calibration 

I should have read!! No issues there then so:

I gather your switch you’ve added is directly off the PCM to ground (i.e not running off another loom) as everyone else mentioned they are a very simple ground switch to activate, nothing can really go wrong there.

So when you don’t have the launch control settings in place does the motor rev freely and not cap at the set launch rpm?

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6 hours ago, [email protected] said:

Just pull the wire out and stick it on ground, then stick it on 12v and datalog what happens.

I have tried this and it does not change 

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Is it possible that if it was originally an auto pcm flashed to manual that the pin isn't connected internally? Someone else with a BA PCM flashed to manual would need to chime in though

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16 minutes ago, nat said:

Is it possible that if it was originally an auto pcm flashed to manual that the pin isn't connected internally? Someone else with a BA PCM flashed to manual would need to chime in though

I am starting to think this too

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17 hours ago, nat said:

Is it possible that if it was originally an auto pcm flashed to manual that the pin isn't connected internally? Someone else with a BA PCM flashed to manual would need to chime in though

I haven't heard of this being a problem before.

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3 hours ago, [email protected] said:

I haven't heard of this being a problem before.

I agree that I’ve never heard of it as a problem either - It would be unlikely that something could have gone wrong in regards to the switch as I’ve even tested my FG one and it’s just straight to ground... it’s just very odd that even with the manual strategy it always puts the PCM in the clutch not depressed state!

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Ok I have tried every thing I can think of.

Putting b5 to earth putting it to battery volts putting pullup resister in putting pull down resisters in toggling clutch switches on/off. launch control switch on/off. Cruise control switches on/off. 

I have even tried pin b4 as this is the clutch pedal switch for a fg. 

I am out of iders.

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Posted (edited)
4 hours ago, Carl said:

Ok I have tried every thing I can think of.

Putting b5 to earth putting it to battery volts putting pullup resister in putting pull down resisters in toggling clutch switches on/off. launch control switch on/off. Cruise control switches on/off. 

I have even tried pin b4 as this is the clutch pedal switch for a fg. 

I am out of iders.

FG is actually still pin b5 for the switch, b4 in an FG is the start enable pin which goes to the starter relay in the power distribution box.

From the sounds of it; I can only think either: a) the PCM is either faulty or if it was an auto pcm then for some odd reason the pin is not hooked up internally (It is so unlikely though to be that! Doesn’t require a solenoid or anything); or b) the strategy is for some reason always ignoring the clutch switch.

whether or not it’s possible to try another manual strategy to cancel anything being software related? (don’t start the car, just flash it and see when ign on if the status changes when logging through your preferred method)

Edited by nat

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7 minutes ago, Carl said:

Ok the manual I have for fg said it was b4 for some unknowin reason.

The pcm was originally an auto one. 

What would be the best way to change the strategy and what to.

Fg Cruise control, various sensors, turbo comp.pdf 155.64 kB · 2 downloads

Did some looking at the proper ford wiring diagrams, and indeed the FG mk2 and FGX both use the switch on B04; however the Ba-FG1 are all definitely on B05; so the document you’ve got is correct but should say from 2012 onward, not 2008!

As for a strategy to try instead, I gather you are already using HAAT0V6 and have licensed it? (BA F6 manual) - I have another calibration of HAAT3VC (BA manual, pretty certain it’s an F6 as it runs even higher boost levels then HAAT0V6) you can get it using the create stock file wizard.

The only issue is for licensing: I’d suggest wait for Roland or Darryl to chime in to let you know as I think it would cost in credit as I believe the calibration OSID is the first 5 digits (HAAT0 vs HAAT3); I wouldn’t suggest going ahead until you’ve got clarification as no point spending a credit if it achieves nothing! Sadly I don’t have a list of any other HAAT0 IDs... my list is old as - around 2012!

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Changing the OSID will cost 2 credits to re-license. Quite a few people have used the HAAT0 F6 in manual BAs with good results. You just need to flip the oil pressure switch scalar or you will have an inverted oil pressure warning lamp, the scalar ID is in a thread somewhere.

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