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Frequently Asked Questions - Traction, Launch & Gearbox Control
 
When purchasing second hand ECUs, please note the following;

If the ECU is still a current issue i.e. advertised on our web site, it can be reprogrammed, costs from £90.00 + VAT per unit.

If the ECU is an older model, it is recommended that the ECU be only used for the type of engine it is already programmed for. If you require an older model reprogrammed, costs are from £140.00 + VAT per unit dependant on the age of the ECU. It can cost more for the unit to be reprogrammed than the purchase of new ECU. In addition, if the unit breaks, the older units (e.g. 900 to 967) are irreparable.


Disabling traction control temporarily for tight hairpins & dry starts
Using launch control for dry starts
How much throttle should I apply when using Launch Control?
Powershift set-up issues
Traction control and launch control and how to use it
Queued Gearshifts
 
Disabling traction control temporarily for tight hairpins & dry starts

Question: As you know, I have become quite a fan of the traction control, but am honestly not such a fan of the launch control on dry tarmac, although I would still like to use traction control on dry tarmac.

The comment of Craig's which I remember, was something along the lines of "holding the launch button down allows you to warm the tyres up", so if this is correct, would it enable me to effectively disengage the traction control for as long as I need to off the start line?

Also, I had real problems at a couple of hairpins in Cork, where I really could have done without the T/C. This got me thinking about whether a momentary push of the launch button could start a timer in the ECU, which would, on very rare occasions only (i.e. start on dry tarmac and at very tight hairpins), disable the traction control....

Does holding down the launch button disable traction control? Whether a momentary push timer of some sort might be something you would consider?

Answer: When holding the launch button down, traction control and launch control is indeed disabled.

Disabling traction control at low speeds should not be required, one driver in particular quite often uses a rally driving style on tight hairpins and has no issues getting the back end of the car to step out.  The traction control is then used to maintain the amount of drift he requires.  Since the traction control settings work on speed difference, if your front wheels were doing for example, 20mph on a hairpin, the rear wheels are able to do 28mph which will allow for a significant drift angle and as the speed of the car increases, this drift angle can be maintained.  Originally we used a percentage of speed difference, this mean that there was too much control at low speed and less control as the speed increased. 

If you really wish to either disable the traction control or modify it, the best solution would be to redesign the launch and traction control wiring and use a switch connected to the handbrake, it would then be possible to do one of two things; either make it operate the same as the launch button and disable it completely when the handbrake is operated or by duplicating a resistor value for one of the 7 sectors, enter a different traction value in to this particular sector e.g. if it is currently set to 8mph, set to say 15mph, then carry out testing to optimise the amount of drift that you require.  Since you are only likely to need this during a corner that may require a handbrake turn anyway.  Also this type of manoeuvre would become easy for the brain to understand under these conditions, rather than having to push buttons in a stress full moment.

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Using launch control for dry starts

Question: I have a question about the use of the launch control on dry tarmac in rally use. It feels incredibly hard on the car which, with two rear wheels each weighing about 20kg (yes, really!), leaves me sitting on the line just waiting for something to break... whilst I can appreciate the time benefit on sprints & hillclimbs, I am not yet convinced of the benefit of launch control on my car on dry tarmac.

Answer: We have customers who have very fragile transmissions.  When using manual launches one particular customer was breaking CV joints, driveshafts and on a couple of occasions even split the transmission in half, once he started using launch and traction control, the transmission problems almost completely vanished.  Another customer, who was breaking crown wheel and pinions also gained the same improvements in component life.  So it appears that a control launch creates less stress than a manual launch, which is controlled by the driver's right foot and the amount of grip at each moment during the launch period, which could vary greatly.  Don't forget that on the sprint cars, the tyres are normally much wider and have far more grip, the number of starts that we have during each day easily goes into double figures, particularly when double driven and so far we have seen no increased wear.

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How much throttle should I apply when using Launch Control?

Question: The launch control is excellent although I have a question relating to the 7 launch sectors. I understand the sectors enable differing revs to be used for different track conditions. Should I be applying full throttle pedal prior to releasing the clutch with launch governing different revs depending on the sector selected? Until now I have only applied about 2/3 pedal prior to releasing the clutch.

Answer: In theory you can use full throttle and the rpm during the launch phase will be taken care of by the ECU.  If you use too little throttle, you stand a chance of the car bogging down and dropping below the target rpm.  This is because the amount of power being produced by the engine is controlled by the amount of throttle opening, giving full throttle will give the maximum amount of power possible at the target rpm selected.  This means you always get a known amount of torque at every sector you use.  If you vary the amount of throttle, the torque will obviously vary and you will get inconsistent starts.

This is what Trevor Willis does and he has commented that when he tries to drive the car during the launch phase modulating the throttle, that the starts are not as good.  One important thing to remember is that quite often lower rpm will give a better start than higher rpm, even though from the drivers seat you may fill the start is quick, the clock is the best way to tell.

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Powershift set-up issues

Question: One of our trade customers was having problems with a powershift set-up on one of their customers cars and asked for some help, he had set up the map using the settings from another car which has worked well.

The car was an Escort with a VX and Elite IL300 box and the description of the symptoms was; "Just been out in the car and it still isn't working correctly, it's very harsh when it comes back on power, not a nice smooth cut at all. It all seems too harsh and needs smoothing out. The setup is just using an ignition cut, cutting the spark, so it's very on and off. The setup allows for torque reduction + recovery, can you tell me a bit more about these settings and also why these aren't been used? There isn't any information available about the MBE settings and if I fiddle with them without knowing their functions, it will end up causing issues."

He also asked: When we have spoken in the past you said you had not found the need to use the torque recovery and that ignition only worked very well.  Hence my using the same options. Could you provide any advice as to possible solutions.  I notice on the paddle shift set ups I have looked at the "Finish Upshift Drum Rotation Threshold" is at 70% but on the flatshifts its 100% - could this be the issue?

Answer: Always make sure you are using the latest software, please check our website.

I suspect you have 2 potential issues; the first problem will be how the power shift is triggered. Quite often some of the gearboxes have an adjustable switch or sensor and what the manufacturer quite often does to ensure the powershift works is to make the switch trigger too early. This means that when the gearstick is pulled that instead of triggering just at the point of disengagement, it is triggered much earlier, this effects both single cut time set ups and full closed loop set ups. When used in the single cut time, it means that the time has to be extended to cover the fact that when the driver pulls the gearstick, there can be quite a length of time from the spark being cut before the dogs of the gearbox are actually disengaging and by the time the gearbox has completed its change, the driver will be able to feel this huge delay making for quite often and uncomfortable gear change. When using the closed loop version the same issue applies, the trigger again will be too early and although the gear change time is able to vary due to the ECU knowing the drum position and able to complete the gear change when it reaches a pre-programmed position, it is extended due to the early trigger.

In order to alter the trigger point, you will need to discuss with the manufacturer of the gearbox how this is done and experiment with the trigger point according to the manufacturer's instructions. This could be done by shims or adjustable screw to move the switch.

Once you have sorted the start point, then you will be able to adjust the cut time if using a single cut set up but because no gear changes are ever the same, care must be taken not to shorten the cut time too much. A single cut is also not suitable for cars that could potentially be wheel spinning during gear change.  It is always best to use closed loop set up using the trigger to initiate the gear change and drum rotation to complete the gear change. This way the MBE system self-adjusts to the variation in time taken for each gear change.

Due to the fact that every manufacturer of gearbox works slightly differently, therefore the gears drum rotation will also vary. You should experiment with the percentage of drum rotation for completing the gear change.  When set to 100%, the power will only re-instated once the gearbox drum has completed its rotation. You can experiment with shortening this value and it will speed up the gear change. Again great care must be taken if the value is set too low, although the gear change would become very fast, if the dogs have only just engaged there is a possibility that damage will occur due to the fact that the power is being re-instated too early. We find that most car gearboxes can go down to 70% of drum rotation and bike gearboxes down to 79%, but it is suggested that you start at 100% and slowly reduce this value due testing.

The difference between cut and retard; cut simply removes all the sparks and retard will retard the ignition so the engine produces no power. Cut is simpler and if all the above are set up correctly, the gear changes should be very nice. If you use retard, it can be smoother but produces other issues; whilst retarded the engine will be producing more heat and if the engine itself is prone to any issues, it could amplify an inherent problem with the engine. Also when the ignition is in a retarded state, the fuel is no longer ignited in the combustion chamber, it will be ignited in the exhaust producing additional noise because of this. A combination of cut and retard can be used but more information, as far as suggested settings are concerning, are within Easimap 6.

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Traction control and launch control and how to use it
Question: Quick question regarding the traction control. Would I be correct in thinking that when it kicks-in, I should not take my foot off the throttle at all (which is the immediate instinct) but continue to apply throttle and let the electronics do all the work?

Answer: Everybody tries to use the traction control in a different way, some drivers assume (usually the slow drivers) that it will make them faster and instead of driving the car normally, drive the car with the pedal flat to the floor and let the traction control do all the work.  The way I use the traction control and many of the quick drivers use it, is to drive the car normally but when the conditions are slightly suspect i.e. the driver is unsure of the amount of grip is available in certain areas, that the traction control will allow them to use slightly more throttle and be less cautious than they would have been.  That way if a patch on the circuit is found to be less grippy than expected, the traction control will give you some extra protection. 

One of the best example of this, is if you are drifting the back end of the car and suddenly hit a patch of oil, you would normally attempt to come out of the throttle to prevent the rear end of the car from producing an excess slide and putting you into a spin, because the traction control can detect this sudden change quicker than you can, it will back the power off and normally allow you to carry on at the same angle of drift without loss of control.  If at the same time you back the throttle off, you will actually get slower and the angle of drift will reduce. 

My suggestion is that the traction control should be used to help you to maintain grip in unforeseen circumstances rather than a crutch to rely on.  Drive the car,  do not change your driving style but experiment under controlled conditions so you get a feel for what the traction control can do for you.  Traction control can not lose you grip, it can only help you to gain grip. 

One last thing that is important with traction control, which many drivers feel including myself, is that when you have a normal start or lose grip is the sensation the driver feels of the car sliding and wheel spinning is quite intense.  When the launch and traction control are working, the effect almost feels as if you are going too slowly, but the only way to tell is against the clock and in most cases the smoother feeling with the launch and traction control working, the car is faster but it just doesn't feel like that for the driver.

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Queued Gearshifts
Question: Does the MBE have an option for queued gearshifts?

Answer: We did consider adding an option for queued gearshifts but have not found it necessary, most drivers who have used our system including those converting from other makes of gearshift systems find ours usually faster on the shifts (mostly due to the integration of engine and gearbox software) and not thought it necessary once tested. My own personal thoughts on queued downshifts is that when you approach a corner, if you don't know what gear you want you would just keep tapping the paddle hoping you would get enough downshift. If you do know which gear you want, you again have to think how many times you have to hit the paddle, if you then approach the corner and something has changed you may have to hit the paddle for more gear changes. All of the these options require additional thought by the driver and these thought trains will be different based on the discipline you are competing in, simple pull and hold means it will only change down safely and if you let go of the paddle, it will stop changing down. If you simply want one gear change, you tap and release the paddle. I have found that if we attempted to queue the gears, if it wasn't safe to downshift when the paddle was hit and a change occurred later, this was very distracting for the driver and he didn't know what point the change would occur. This was particularly uncomfortable if an unexpected gear change happened when the driver was making an unexpected change in direction avoiding another car or obstacle.

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