The effect of TM intervention on my C6Z at the drag strip is certainly more than a loss of just a few rwhp. I supect the loss is .2-.3 seconds.

Keep in mind that the dyno won't reflect the invocation of TM because (1) the acceleration is smooth, (2) WOT comes on at 1:1 gearing and (3) the rear wheels stay hooked, since the rear is strapped down. So the conditions that would invoke TM are not encountered on the dyno anyway.

So measuring the effect of the tune that removed TM and then attributing that delta as the max-loss effect of TM is invalid.

Ranger

 

yiippeeeee ........huurraayyyyy....wow..i'm now really really impressed with my '05. according to this chart my '05 and the '06 z06 are both limited to the same output. watch out z06 here i come. hahahahaha..

 

Yeah, you just have to back of before 3000 RPM

I thought about the same thing when he first posted, but I really was ready to let it die.

 

I wonder if you do a power shift and don't push the clutch in all the way you can fool the TM into thinking your just on the dyno...... couldn't help it.

 

True.

 

You don't understand, just because your car has 400 pounds of torque does not mean it will not spike higher. Your car can hit well over 600 pounds when you dump the clutch and between shifts if the rpms are higher than the flywheel is spinning.
You can't break down a door by simply pushing on it, but if you get a running start you can, are you stronger when you're running? No. Not that I'd expect you to get it but I figured I'd try.

 

Not sure how the rpm's can be different than flywheel speed and let’s not confuse inertia with torque. Also you’re not stronger when running you just added velocity to the energy equation and it’s most significant because it’s a squared factor.

 

My mistake, I meant clutch

I think thats what I said. Therefore even though the torque is set more than the car has on a dyno, the initial shock of the torque is much greater than the car acutally has

 

and if we look at the provided chart it apparently shows that neither will be permitted to exceed 281 ft lbs at 3000 rpm. it would be nice to see the rest of the figures up to 6k.

i'm not sure how your engine is gonna produce more that it's maximum rated output. the 'impact' or 'shock' to the rest of the driveline system will be greater than the engine output during a sudden impact or engagement, i.e dropping the clutch.

i'm still wondering how the system is calculating the horsepower and or torque. how does the ecm calculate hp and trq.

if the assumptions about 'exceeding rated load during shock engagement' are true then 'building up the driveline' would yield zero results until the computer is told about said changes.

 

While I agree with what you are saying if the dyno run is performed "normal". However bang it through the gears getting into 4th gear and you will likely see results like the ones in the picture below. I have two more runs that gave almost identical results. When slowly taken up to 4th then going WOT the car put down normal numbers. I can't find those graphs right now but as I recall the numbers were around 345/348 under normal dyno conditions.

 

Those are some seriously interesting graphs.

I've never seem anyone hammer the throttle until 1:1 gear is reached. Please tell us why you did. An experiment?

Please confirm your tranny type and mods, if any.

Anything on coolant temps on the pulls?

TIA,

Ranger

 

We were just experimenting with the car.

The car at the time was bone stock with a 6 speed manual tranny.

It's hard for me to remember the exact coolant temps but I believe it was in the 190's when we started the runs. The car was allowed to cool for the other two runs that I mentioned with almost identical results.

 

THe engine will never produce more than it is capable of. But we are not measuring engine hp/tq we are measuring RWHP/TQ. By doing a dyno run at 1:1 we come up with engine HP minus drive line loss. But if you are in other gears you will exceed the engines rated torque at the tires. Slipping the clutch or the torque multiplication from an auto are examples of that in addition to gear multiplication. This is also IMO why we see TM being more intrusive on the auto's, it has it's own computer and is probably talking to the ECM.

 

I have not read all the threads concerning this issue so forgive me if I express the same sentiments as others. I have an 06 MN6 Z51. I don't sense any lag when shifting at high RPM. I shift at close to 6500 RPM and the car continues to accelerate well with each passing gear. If there is a torque management program then it is there to protect the car. I am all for protection of this sweet machine. In my estimation, the car is fast enough. Maybe too fast.

 

I am going to post once to try to offer an idea for TM doubters to consider, and then I'll leave it alone. I am not interested in debating, arguing hypotheticals, etc. just in providing some food for thought.

Zig, you have asked much the same question as above time and time again. I don't necessarily blame you -- if there is a single load cell hidden between the third member and a frame rail with a connecting arm between them, it would be cool if someone were to uncover it.

But there is obviously no such load cell, or LVDT, or strain gauge, or other direct torque measuring transducer on the C6.

There is no need for such a thing to accomplish the 'mission' of managing the output so as to limit damage related to excess torque excursions.

Knowledgeable people have said here many times, quoting the manual, tuner menus, etc "It is a system." We already have (to answer a previous question) not one accelerometer on board, but several. You have them as inputs to HUD G meter for lateral forces. You have 'em in the air bag system. There are many other sensors that detect throttle position, temp, knock, speed, RPM, etc, that when the direct input these many sensors provide is combined with some logic, inference and algorithms, it is not too difficult to generate a feedback system that adjusts the timing, fly by wire throttle, fuel flow, brakes, and/or other items so as to mitigate shock damage to driveline components.

To make such a system, the units of measure (or outputs) do not need to be in the form of calibrated SAE HP, or NIST traceable torque in newton meters, available on a single digital readout that is secretly hidden, and therefore TM can't exist unless someone yanks it out by the wires and lays it on your desktop.

If you are interested, you might read a little about analogous control systems that do amazing things with physical sensors and inference, such as 'black box' inertial dead reckoning nav systems that predated GPS.

Again, none of this is meant to argue, or to refute anyone. just trying to point out that there is no need at all for a single part number to exist titled "Torque sensor transducer and computing module" for TM to be a "real" system.

 

thank you very much for such a good response.

i will agree wholeheartedly that the possibility exists for such a system and it has been most fun trying to determine how it operates.

while i agree that the 'function' may be the result of multiple sensors and inputs it may also be possible to skew the results obtained by those same sensors if one knew how the information was used.

don't get me wrong, if TM exists, i would love to know how to drive around it.

i'm simply trying to find out how it works, what causes it to trigger, how to replicate the event, how to drive around it, what components may be used, what would happen if such-and-such was done, etc, etc.

so far i haven't seen anything from 'Delphi' or the driveline or the rearend manufacture that details components that could be used to 'limit' or measure the input through the driveline. if the computer is using figures from sensors not in the driveline then one would be able to skew those results if he knew how it calculated the results.

if pitch and yaw are used to determine driveline stress, then beefing up the suspension would 'change' the results and likewise for other sensors.

i'm not trying to argue just trying to figure this darn thing out instead of just accepting that it's there because someone 'claims' it to be.

remember, a long time ago all the experts claimed the world was flat.

 

what does the engine care how much power is at the wheels, the engine is only concerned with the engine. if the 'load' on the engine is greater than the 'output' of the engine the engine will die. are we saying that the 'load' generated by the 'gearing' selected and the 'traction' (resistance) is causing the 'load' to exceed the 'output' potential of the engine.

or in other words, doesn't the gearing always multiply the engine output ? if the engine is using the gearing multiplier and limiting the output to less than the 'rated output' of the engine we really wouldn't go all that fast.

the 'auto' transmissions have a 'tm' system build into it simply by nature. how does an automatic transmission know to change gears. one type or another of torque management has always been in the automatic transmissions, that's how they work.

 

I beleive this is the place they dreamed up the commercial "No but I stayed at a Holiday Inn Express last night"

 

IF there is TM ?
Just how many years does it have to exist before this whole topic bcomes outdated with even newer TM designs.
There is all types of TM devices and methods in all makes of cars and trucks today

Automotive Powertrain Torque Sensing – System Control Optimization
Modern electronically controlled transmissions typically utilize “torque” as the basis for transmission shift control.
Today’s systems often rely on empirically based look-up tables for torque measurement estimates. However, it is often difficult to accommodate all the potential factors that can affect the efficient operation of the powertrain system. New engine technologies, such as, cylinder de-activation and variable valve timing, sudden acceleration/deceleration, HVAC system on/off usage and various environmental effects all contribute to this issue, while service wear also affect both engine and transmission characteristics over time.

Changes in acceleration during a power-up or downshift can often be significant. Power-off shifts are typically characterized by an audible noise in the driveline system. Achievement of both smoothness and durability in a transmission system design is typically expensive and space consuming. Powertrain Torque Control can often improve responsiveness and fuel efficiency without the "shift shock" and sluggish driving characteristics of many automatics. Significant fuel economy and performance gains are also expected benefits of more efficient automatic transmission ratio changing.

It appears that more and more of the torque transfer that occurs during an upshift or downshift in today’s passenger car automatic transmission is electronically controlled. Sensors that can detect pressure, temperature, position and speed have seen a rapid deployment, both internal and external to the automatic transmission housing. Electronic transmission control is a seemingly absolute necessity as passenger car automatic transmissions migrate from 3 and 4 speed planetaries towards either 5 to 7 speed gearsets or other new forms of efficient and compact gear trains.

In addition to increased forward ratios the emergence of Advanced Automatic Transmission Systems such as Continuously Variable Transmission (CVT), Infinitely Variable Transmission (IVT), Automated Manual Transmission (AMT), Double Clutch Transmission (DCT), and Hybrid Electric Vehicles (HEV) often require significant sensor content for proper operation. The addition of real-time torque measurement promotes the optimization of power train system management.

As 4WD/AWD vehicle systems become more sophisticated and fully active systems become more prevalent there is a pressing need for improved torque sensing capability in driveline applications (Including wheel corners). Increasingly accurate, active torque management can provide significant improvement over passive, electro-mechanical or hydraulic approaches. Torque management is expected to be a key factor regarding improved vehicle performance, stability and safety.

Real Time Torque Sensor
An attractive sensor for an automatic transmission would be a torque sensor that is capable of measuring real time torque at millisecond or better update rate. This sensor would be located at one or two essential points on the automatic transmission, i.e. at the input shaft or the output shaft or possibly both. Knowing the real time torque, the transmission ECU would have the information necessary to continually update the transmission algorithms to promote smooth and or fast shifts. All other material information can be typically derived from the engine sensors.

With one or two torque sensors properly placed, the automatic transmission ECU would no longer need to infer shift timing from remote sensing points. The troublesome real time delays that take place between the transmission ECU, the pressure sensors and solenoid valves would no longer be a significant issue for the transmission designer.

Existing torque sensors principally include resistance strain gauges (requiring slip rings for interrogation) and non-contacting sensors based on the principles of magnetostriction. However, as of this writing, torque sensors within the automotive world have been primarily used for the laboratory testing and evaluation of engine and transmission systems and their control algorithms.

Over the past few years, research and development has been applied to the provision of an increasingly reliable and accurate, low cost torque sensor technology for vehicle OEM applications. Surface Acoustic Wave “SAW” sensors provide wireless interrogation for applications such as: transmission input shaft torque, transmission output shaft torque and driveline torque for 4-wheel-drive (4WD) and All-wheel drive (AWD) vehicles. Essentially, a torque sensor module can often be integrated within the powertrain, and torsional strain monitored, for proportional real time torque measurement and corresponding system adjustments.

Design Integration
Transmission sensors often find application in a variety of challenging locations and environmental conditions. Many sensors are found outside of the transmission case, submerged in the oil cavity area or nestled near the rotating members. The internal sensors are typically subject to the same conditions and specifications as the friction devices, transmission oil and planetary gearsets. The operating environment can, in certain instances, have a thermal range of –40°C to 150°C with simultaneous shock, vibration, EMC, humidity, galvanic corrosion and exposure to hostile fluids. SAW torque technology offers a robust package configuration for proper operation in many such environments.

A key factor regarding successful sensor design is knowing how the automatic transmission is constructed. There are three principal assembly directions: drop in component from the pump or torque converter opening, sensor installed along the outside of the case, or sensor placed in the ECM valve body package via the oil pan. Where possible the sensor design should not interfere or detract from the assembly pattern of an automatic transmission. With SAW torque technology a compact package design typically provides ease of integration with existing system configurations. Various sensor mounting options are available allowing engineers flexibility for system integration.

Precise knowledge of the peak torques sustained by any element of an automotive powertrain will enable mechanical designs to be optimized in terms of the dimensions of shafts and disc components thereby offering weight and real cost savings.

Conclusion
Torque sensors and wireless interrogation based on surface acoustic wave (SAW) technology have been developed over the past decade to promote robust, accurate and cost effective monitoring and feedback for the enhanced control of tomorrow’s automotive transmissions.

I highly doubt people think SAE added TM paramteres in our cars or several vendors making TM methods just for GM and the Corvette

 

You bet! That's the objective -- find some ways to tweak it, that don't blow the car up
You join the many!

You are correct! I am finding that it is a most difficult thing is to 'object without being objectionable' in forums. I'll be the first to admit that I am used to being accepted as the technical authority in my domain (certainly not cars!), and when face to face, it is easy to see humor, inflection, etc., so it's easy for simple disagreements (or even agreements but using different words ) to spin up, especially when checkable, verifiable facts are few and hard to find. Well, I said I would post once, and here I am....

Over and out

Cheers: