Torque Management
#1
TECH Addict
Thread Starter
Torque Management
How does the PCM manage the engine’s torque output when torque management is active and is torque management something that can be tuned to help with traction? Has anyone tried using torque management to help with traction?
#2
TECH Resident
Usually by throttle control, but may also be spark. Yes TM can be used to control traction, but its not real accurate. i.e. whats ok on a dry road may spin up on a wet road.
#4
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On the 4th gen F-bodies TM is purely spark retard.
You have tables telling how much torque to pull
out under shifts, you have tables that tell how
much spark retard to apply for such-and-such
demanded torque reduction.
But on this platform all of this knows nothing
about traction. That's the province of the TCS
"brain" in concert with the ABS system, and TCS
applies a layered strategy of spark retard (the
most nimble), throttle cable pullback (the pain
in everybody's ***, especially A4s where this
will force an upshift) and brake apply (don't go
there; I played with TCS defeat way way back
when and made one track pass with the brakes
applying this way; sucked / embarassing).
Anyway, short answer is that both are too dumb
to be useful in this way. Best I have found is to
give traction control spark retard more latitude
and remove the throttle cable. More spark retard
gives more useful authority. Not enough maybe to
make matted pedal stick, but at least better
behaved than stock.
TM does help a wimp A4 survive. Getting shift times
to minimum may make you not notice TM as much
(leisurely shifts extend the time of torque-cut).
But as far as a traction control actor, this is not a
very good one.
You have tables telling how much torque to pull
out under shifts, you have tables that tell how
much spark retard to apply for such-and-such
demanded torque reduction.
But on this platform all of this knows nothing
about traction. That's the province of the TCS
"brain" in concert with the ABS system, and TCS
applies a layered strategy of spark retard (the
most nimble), throttle cable pullback (the pain
in everybody's ***, especially A4s where this
will force an upshift) and brake apply (don't go
there; I played with TCS defeat way way back
when and made one track pass with the brakes
applying this way; sucked / embarassing).
Anyway, short answer is that both are too dumb
to be useful in this way. Best I have found is to
give traction control spark retard more latitude
and remove the throttle cable. More spark retard
gives more useful authority. Not enough maybe to
make matted pedal stick, but at least better
behaved than stock.
TM does help a wimp A4 survive. Getting shift times
to minimum may make you not notice TM as much
(leisurely shifts extend the time of torque-cut).
But as far as a traction control actor, this is not a
very good one.
#5
TECH Addict
Thread Starter
Thanks jimmyblue for a very educational answer. I did not know that when the TCS is activated that spark retard is being used along with the throttle cable being pulled back. I thought only the throttle cable was used for traction control. Is the TCS spark retard tunable with tuning software? If I understand you correctly TM only comes into play when the trans is shifting?
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#8
I asked this on another forum but haven't got much back. Can you use the TQ management to pull a couple degrees in 4th/5th gear for high speed runs? I have an M6 GTO and it seems to not be able to recognize which gear or what RPM I am at when pulling timing. Just want a few degrees pulled for high load situations but still be able to keep the advance for gears 1-3.