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Hey roland. Having the same issue. When you say hard cut and soft cut limits are too far apart what do you mean exactly? What is the soft cut limit? And what’s the hard cut limit?

it got set up following the bf launch control guide if that matters

Edited by Cooper
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Eg your normal rev limit is:

auF0144 RPM Limit

The rpm limit is then extended by the value found in auF11698 for 1 second.


Then if it continues to climb for any reason to the value in auF0133 (the hard cut) it will cut all injectors.

auF0133 Enable fuel cut to limit RPM after this RPM point.

Eg for 1 second the rpm limit will be 6150. After 1 second the rpm limit will drop to 6000.

Eg it will bounce between 6000/6150 and 6250 using PID injector control. Eg cutting 1 injector, 2 injectors... all the way up to 6 injectors. If at any time it gets to 6250 the PID controller is disabled and it instantly cuts all 6 injectors.

When in launch control it switches out 6000/6150 (auF0144 + auF11698) with the value found in auF2035 Fuel cut RPM for launch

So the range the PID controller will operate in is 6000-6150 -> 6250 so you can change this to change the amount it can bounce. To change the rate at it which it bounces you need to change the Proportional gain for the rev limiter.

auF1689 Proportional gain for powertrain protection over n

I have not tested this but I would assume larger numbers will make it bounce faster, lower numbers will bounce slower.

There is also an integral gain, you wouldn't normally need to touch this.

If your torque/spark/speed density tables are up the creek then this will will affect the error term and hence how fast it bounces as well. Eg any large step changes in spark or airmass will make it cut too much or too little injector and the rpm will not be consistently controlled.

So to answer your question. There is a lot of things that will change the rate it bounces and far it bounces. 

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