dynoing with tc and ah
Thread Starter
Instructor
Joined: Mar 2005
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From: Oklahoma City OK
dynoing with tc and ah
Is there a problem with dynoing with tc and ah enabled? The reason I ask is yesterday I went to the dyno and did not disable them. The torque seems a little low.
This is with a cam and LT's.
I checked in HP Tuners, and under the Torque Management tab the Max torque is set at 350ft-lbs. It is electronic throttle control limited.
Here is the explanation from HPT help files.
Max Torque: Maximum allowed engine torque for Electronic Throttle Control fitted vehicles. This value is also used to control a torque based PCM output, this is used on some Holden vehicles to reduce Fuel Pump voltage when torque is below this value. WARNING: increasing this value on those vehicles will result in reduced fuel pressure, lean conditions and possible engine damage during high torque operation.
For clarification I own a 2001 Z06.
This is with a cam and LT's.
I checked in HP Tuners, and under the Torque Management tab the Max torque is set at 350ft-lbs. It is electronic throttle control limited.
Here is the explanation from HPT help files.
Max Torque: Maximum allowed engine torque for Electronic Throttle Control fitted vehicles. This value is also used to control a torque based PCM output, this is used on some Holden vehicles to reduce Fuel Pump voltage when torque is below this value. WARNING: increasing this value on those vehicles will result in reduced fuel pressure, lean conditions and possible engine damage during high torque operation.
For clarification I own a 2001 Z06.
Le Mans Master
Joined: Dec 2000
Posts: 9,919
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From: Hot Springs AR
I don't see how traction control could *not* have been disabled and make any kind of dyno run. Since the front wheels are stationary, as soon as the rears start moving the car will interpret that as wheel spin and pull power.
Or, I'm about to learn something.
HTH, and have a good one,
Mike
Or, I'm about to learn something.
HTH, and have a good one,
Mike
Thread Starter
Instructor
Joined: Mar 2005
Posts: 163
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From: Oklahoma City OK
Originally Posted by John@SDPC
One of the methods the PCM uses to control power is by pulling timing. Timing reductions will kill power. Did the operator notice any messages about Active Handling while running the dyno?
I really have no idea, thus the reason I posted here.
Thanks,
Jeremy
Le Mans Master
Joined: Dec 2000
Posts: 9,919
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From: Hot Springs AR
It sounds like the operator put the car into Competition mode (TC off, AH on) to make the runs. You're correct, TC works by closing the throttle, I don't think it messes with timing at all.
I don't think the torque management algorithms are engaged on the C5s with M6 trannys, only A4s. C6s are a different story.
In any case, is this the first time you made any pulls on this dyno? Or, do you have a baseline (before the cam and LTs) to compare? You're showing about 400 hp at the wheels, which would translate into about 460 at the engine. Seems in the ballpark to me for a baseline 385 hp engine with those mods.
HTH, and have a good one,
Mike
I don't think the torque management algorithms are engaged on the C5s with M6 trannys, only A4s. C6s are a different story.
In any case, is this the first time you made any pulls on this dyno? Or, do you have a baseline (before the cam and LTs) to compare? You're showing about 400 hp at the wheels, which would translate into about 460 at the engine. Seems in the ballpark to me for a baseline 385 hp engine with those mods.
HTH, and have a good one,
Mike
Former Vendor
Joined: Mar 2006
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If you have scan data from the runs, I would check throttle position, timing, MAF, and MAP values. If the PCM closed/limited the throttle, the MAF and MAP readings should be lower on the run when AH/TC kicked in.
I could be wrong, but I am fairly certain the PCM uses both ETC controls and spark retard to control/limit the torque being produced. I thought this was the purpose of tables like TCS Spark Retard, but my wife tells me I am wrong all the time. So, this wouldn't be the first time.
I could be wrong, but I am fairly certain the PCM uses both ETC controls and spark retard to control/limit the torque being produced. I thought this was the purpose of tables like TCS Spark Retard, but my wife tells me I am wrong all the time. So, this wouldn't be the first time.
Last edited by John@SDPC; Apr 27, 2006 at 09:59 AM.
