Traction control retards timing cuts spark anti lag 2 step sounds

[2ndViper]

So last night I drove the car with the windows down and I'm pretty sure that when I rolled into the throttle hard and started to spin the car did what seemed to sound like a 2 step or anti lag.... I took out the stock mufflers and this was the first time I had heard it so aggressively but I assume this is part of the cars "traction control" working? Needless to say I did it a hand full of times after only because of the fireballs from the exhaust in my mirrors and the fun noises but I'm curious as to what is actually happening if anyone knows.

[slowhatch]

So last night I drove the car with the windows down and I'm pretty sure that when I rolled into the throttle hard and started to spin the car did what seemed to sound like a 2 step or anti lag.... I took out the stock mufflers and this was the first time I had heard it so aggressively but I assume this is part of the cars "traction control" working? Needless to say I did it a hand full of times after only because of the fireballs from the exhaust in my mirrors and the fun noises but I'm curious as to what is actually happening if anyone knows.

Turn off all stability systems do it again.

If its prevalent, backfiring out of one bank only, you likely have one of 2 issues; Cracked spark plug, or a boot that has backed off the spark plug due to a looser then necessary ball/seat connection.

[Jack B]

Some insight - even with ESC off, the pcm dramatically pulls throttle when there is wheel slippage, this is even with the pedal on the floor. None of this causes a back fire.

[Arizona Vipers]

Some insight - even with ESC off, the pcm dramatically pulls throttle when there is wheel slippage, this is even with the pedal on the floor. None of this causes a back fire.

Agreed. The way the Viper does it is pretty seemless though, not as bad as most cars. I don't really "feel" it on the track, but I just know when my car is slower on the straights. Same on my '13 with everything shut off and ACR in track mode.

[Jack B]

Agreed. The way the Viper does it is pretty seemless though, not as bad as most cars. I don't really "feel" it on the track, but I just know when my car is slower on the straights. Same on my '13 with everything shut off and ACR in track mode.

i have dozens of logs with the foot on the floor and the throttle at 50%. or less. The key is, do not lose traction, then, no intervention.

[Bruce H.]

i have dozens of logs with the foot on the floor and the throttle at 50%. or less. The key is, do not lose traction, then, no intervention.

I'm surprised Chris Harris was able to drift the ACR as well as he did in his review of it, as well as drifting in that promo video with Reese Millen.

I'm guessing the Arrow ECU doesn't have as aggressive intervention?

[dewilmoth]

i have dozens of logs with the foot on the floor and the throttle at 50%. or less. The key is, do not lose traction, then, no intervention.

Are you saying with everything completely off the car will still veto decisions made by the right foot? If so I’m really surprised that hasn’t been discussed more. Is it some sort of torque management “feature” and not directly related traction control?

[ViperGeorge]

Are you saying with everything completely off the car will still veto decisions made by the right foot? If so I’m really surprised that hasn’t been discussed more. Is it some sort of torque management “feature” and not directly related traction control?

When ESC/Traction is off, it is off. It does not interfere. One of the nice things about the Viper.

[Jack B]

I'm surprised Chris Harris was able to drift the ACR as well as he did in his review of it, as well as drifting in that promo video with Reese Millen.

I'm guessing the Arrow ECU doesn't have as aggressive intervention?

i have the Arrow pcm.

[Jack B]

Are you saying with everything completely off the car will still veto decisions made by the right foot? If so I’m really surprised that hasn’t been discussed more. Is it some sort of torque management “feature” and not directly related traction control?

If you do not log pedal and throttle you will not see it or feel it. where i see it the most is in 1st and 2nd gear, that is where the toque to the wheels is the greatest.

[Jack B]

When ESC/Traction is off, it is off. It does not interfere. One of the nice things about the Viper.

That is not true, i graph it all the time. i am traveling, when i get home, I will post a graph, again, you cannot feel it. As stated, i have only seen it in 1st and 2nd gear, there is probaly not enough straight line tq past 2nd gear to break traction.

[dewilmoth]

That is not true, i graph it all the time. i am traveling, when i get home, I will post a graph, again, you cannot feel it. As stated, i have only seen it in 1st and 2nd gear, there is probaly not enough straight line tq past 2nd gear to break traction.

Can it be eliminated in HP tuners? I’d be curious to know whether you see the same trend in Arrow stage 2 Cars. Does it always happen in first and 2nd gear or only with a loss of traction? I’m wondering if it’s really related to the traction control or if the engine is just purposely tuned that way for some reason in 1st and 2nd?

[Jack B]

Can it be eliminated in HP tuners? I’d be curious to know whether you see the same trend in Arrow stage 2 Cars. Does it always happen in first and 2nd gear or only with a loss of traction? I’m wondering if it’s really related to the traction control or if the engine is just purposely tuned that way for some reason in 1st and 2nd?

HPT cannot access the ESC. It is hard to separate loss of traction from stability.

[SRT_BluByU]

Thats a pretty big accusation.. I believe SRT/Dodge is on the record saying traction control if fully defeatable on all SRT vechicles. may sound silly but are you sure you had it in full off? also are you sure this isnt just torque manament keep folks from speed shifting and splitting the trans in half?

[ViperGeorge]

That is not true, i graph it all the time. i am traveling, when i get home, I will post a graph, again, you cannot feel it. As stated, i have only seen it in 1st and 2nd gear, there is probaly not enough straight line tq past 2nd gear to break traction.

I know Erich Heuschele from SRT. He developed the system for the Viper and told be without reservation that it is off when you turn it off. I'll reach out to him again maybe I misunderstood him. I've never felt it interfere though when off.

[Jack B]

I know Erich Heuschele from SRT. He developed the system for the Viper and told be without reservation that it is off when you turn it off. I'll reach out to him again maybe I misunderstood him. I've never felt it interfere though when off.

i will attach a log tonight, it is black and white. I am not trying to argue, look at at the data, then, try and refute it. As i said, i have dozens of this type of event on paper. When it pulls throttle, it also pulls timing.

[Bruce H.]

I know Erich Heuschele from SRT. He developed the system for the Viper and told be without reservation that it is off when you turn it off. I'll reach out to him again maybe I misunderstood him. I've never felt it interfere though when off.

I remember hearing or reading Eric dicussing traction control being completely defeatable, and I also heard that federal law mandates that ESC cannot be fully defeated. As the two are so closely related I'm not surprised that Jack's logs seemingly contradict Eric. His further explanation would be helpful.

[ViperGeorge]

Here's what Erich says:

"When it is off, it is off. The only systems that may come in to cut torque are BLD if he is spinning one rear tire and not the other if the LSD is worn out or power hop mitigation if he is hopping the wheels."

Update on BLD from Erich. LSD is Limited Slip Differential.

"Brake Lock Differential. On cars with open diffs, the brakes are used if on a split mu surface to transfer torque to the drive wheel with traction. It is still enabled on Viper but doesn’t come in to play unless the ViscoLok is not working. It reacts to one wheel slipping and not the other and engages the slipping wheel’s brake. Come to think of it, BLD does not reduce engine torque."

[SRT_BluByU]

sounds like what youre seeing is torque managment...

[ViperGeorge]

sounds like what youre seeing is torque managment...

Hmmm, except Erich states that BLD does not effect engine torque on the Viper. Custom tune issue?

[Steve M]

Hmmm, except Erich states that BLD does not effect engine torque on the Viper. Custom tune issue?

Since Jack is running a 9.0L stroker, I'd hope that Arrow would have addressed it.

[ViperGeorge]

Since Jack is running a 9.0L stroker, I'd hope that Arrow would have addressed it.

Don't know what impact the 9.0L would have other than to add a bunch more torque and HP. I've never known Erich to be wrong about the Viper especially on a system he developed. If he says the ESC/Traction is off when it is switched off I have to believe he knows what he is talking about. This would leave me to think there maybe something else causing the effect Jack is seeing in his log. I don't doubt he is seeing it but I don't know what would cause it. Even if Jack's limited slip wasn't working it would only cause one brake to be applied, it shouldn't cause a loss of engine power.

[Steve M]

Don't know what impact the 9.0L would have other than to add a bunch more torque and HP. I've never known Erich to be wrong about the Viper especially on a system he developed. If he says the ESC/Traction is off when it is switched off I have to believe he knows what he is talking about. This would leave me to think there maybe something else causing the effect Jack is seeing in his log. I don't doubt he is seeing it but I don't know what would cause it. Even if Jack's limited slip wasn't working it would only cause one brake to be applied, it shouldn't cause a loss of engine power.

When you are trying to push the limits, sometimes things happen that no one expects. Most people don't log any type of data, so they'd never know. The unfortunate downside is that once you have the data, what do you do about it? And then there's always wanting MORE data, and not being able to get it. Like logging the left and right rear VSS's independently...I'd think only Dodge would have the equipment to do that.

[Jack B]

Here is a log for a shift from 1st to 2nd. For reference, the data boxes display all the log parameters. I hid some PIDS to make it easier to review. Notice the flat red line at the top, that is the pedal on the floor, the pedal is on the floor at 91% and the throttle is full open at 82%. Also note the speed actually slows down (with pedal to floor) as the throttle and timing are pulled. This portion of the log is 1.8 seconds. The 7000 rpm in the box is my shaft speed, not engine rpm, plus, it is only accurate in 1st gear.

29509

[SRT_BluByU]

all the other srts have torque managment to limit torque momentairly of engagment of clutch to reduce driveline stress contributing to longer durability.. i wouldnt be suprised if it was the same for the vioer.. this is different than esc

[Jack B]

all the other srts have torque managment to limit torque momentairly of engagment of clutch to reduce driveline stress contributing to longer durability.. i wouldnt be suprised if it was the same for the vioer.. this is different than esc

This is not at max driveline torque, this is where the pcm senses wheel slippage.

[ViperGeorge]

Unfortunately Erich understandably won't ever comment on a modded car. Probably something to do with liability and the fact that they haven't tested the car with those mods. If we had those same graphs for a bone stock Viper then we might get some better explanation.

[Jack B]

Unfortunately Erich understandably won't ever comment on a modded car. Probably something to do with liability and the fact that they haven't tested the car with those mods. If we had those same graphs for a bone stock Viper then we might get some better explanation.

George:

It was doing the same thing on my stock G5. I have the same recorded events from 2013 and 2014, it is just worst now because it loses traction more often.

[ViperGeorge]

Here is a log for a shift from 1st to 2nd. For reference, the data boxes display all the log parameters. I hid some PIDS to make it easier to review. Notice the flat red line at the top, that is the pedal on the floor, the pedal is on the floor at 91% and the throttle is full open at 82%. Also note the speed actually slows down (with pedal to floor) as the throttle and timing are pulled. This portion of the log is 1.8 seconds. The 7000 rpm in the box is my shaft speed, not engine rpm, plus, it is only accurate in 1st gear.

29509

Jack, As I'm not an expert on logging could you give me a more complete description of the graphs? Or do you have data tables you could share? There are no scales on the graphs so I really don't know what I'm looking at. If you have the same data from a stock 13 or 14 I can ask Erich what he thinks. Are you speed shifting or are you lifting to shift? Are the dips in the graphs at the shift point?

[Jack B]

George:

1. I have labelled all the important PIDS (rpm, pedal, throttle, timing and mph)

2. Look at the small boxes, those give the data from the vertical line that is attached to the box.

3. The red line at the top will show 91%, that is an absolute value and equates to 100% pedal.

4. Notice the way the throttle and the timing both go south after the shift, this is while the pedal is on the floor.

5. In addition, the mph actually drops a little, even when the pedal (red) is on the floor.

6. Keep in mind this is immediately after the wot 1-2 shift, it is also very typical for the car's rear to move a bit to one side, that is because there is some tire spin. All of this is in-detectable unless you log.

7. Like Steve M said, even if we know it is there, how can we change anything? I thing it is a good idea that you show this to Erich. The graph and my explanation above is all he needs to give us an answer, isn't life all about learning.

8. I have already talked with an individual on the original G5 design team (multiple times) and he thought it was normal.



Jack, As I'm not an expert on logging could you give me a more complete description of the graphs? Or do you have data tables you could share? There are no scales on the graphs so I really don't know what I'm looking at. If you have the same data from a stock 13 or 14 I can ask Erich what he thinks. Are you speed shifting or are you lifting to shift? Are the dips in the graphs at the shift point?

[ViperGeorge]

George:

1. I have labelled all the important PIDS (rpm, pedal, throttle, timing and mph)

2. Look at the small boxes, those give the data from the vertical line that is attached to the box.

3. The red line at the top will show 91%, that is an absolute value and equates to 100% pedal.

4. Notice the way the throttle and the timing both go south after the shift, this is while the pedal is on the floor.

5. In addition, the mph actually drops a little, even when the pedal (red) is on the floor.

6. Keep in mind this is immediately after the wot 1-2 shift, it is also very typical for the car's rear to move a bit to one side, that is because there is some tire spin. All of this is in-detectable unless you log.

7. Like Steve M said, even if we know it is there, how can we change anything? I thing it is a good idea that you show this to Erich. The graph and my explanation above is all he needs to give us an answer, isn't life all about learning.

8. I have already talked with an individual on the original G5 design team (multiple times) and he thought it was normal.

I'll see what he says and let you know.

[Arizona Vipers]

Maybe Ninjaneer, Calvo's motec tuner can chime in here.

[SRT_BluByU]

at wot with the accelerator pedal floored immediatly following clutch engagment all srts briefly close the throttle blades.. as do corvettes and camaros.. thats to reduce driveline stress.. normal imho and not related to esc. do a search on any of the lx boards (challenger talk, lxforum, etc) or corvetteforum and youll discover lots of info on this.. from what i recall it can be tuned out with hptuners

[Jack B]

at wot with the accelerator pedal floored immediatly following clutch engagment all srts briefly close the throttle blades.. as do corvettes and camaros.. thats to reduce driveline stress.. normal imho and not related to esc. do a search on any of the lx boards (challenger talk, lxforum, etc) or corvetteforum and youll discover lots of info on this.. from what i recall it can be tuned out with hptuners

it does not happen above 2nd gear where there is traction. It actually looks like the logs from my G2. In some cases the throttle is held back for over 1 second.

HPT is very limited on the G5. I used HPT early on and the only throttle tables you change dealt with removing the delay between the pedal and the throttle and that created a lot of CEL. The HC reflash actually fixed that latency issue.

[ViperGeorge]

at wot with the accelerator pedal floored immediatly following clutch engagment all srts briefly close the throttle blades.. as do corvettes and camaros.. thats to reduce driveline stress.. normal imho and not related to esc. do a search on any of the lx boards (challenger talk, lxforum, etc) or corvetteforum and youll discover lots of info on this.. from what i recall it can be tuned out with hptuners

I'm no expert but this sounds logical. I'm waiting for a response from Erich.

[Jack B]

I'm no expert but this sounds logical. I'm waiting for a response from Erich.

George:

That is not what is happening, this is a long-time dramatic loss of throttle that coincides with a drop in timing and it only happens when the car loses traction. If it looks like a duck, quakes like duck and swims like a duck, it is a duck.

[ViperGeorge]

This is what Erich says:

"OK. If he is powershifting near redline, the throttle will be cut as the engine RPM flares to the rev limiter. That’s how the rev limiter works on electronic throttle cars. Besides cutting spark and/or fuel, which is all you could do on engines with a throttle cable, we can now also control the throttle blades."

[Jack B]

This is what Erich says:

"OK. If he is powershifting near redline, the throttle will be cut as the engine RPM flares to the rev limiter. That’s how the rev limiter works on electronic throttle cars. Besides cutting spark and/or fuel, which is all you could do on engines with a throttle cable, we can now also control the throttle blades."

George:

The throttle does not cut when you hit the limiter, the injectors cut. In this case I did not hit the limiter, plus, my 3rd and 4th gear shifts were identical to the 2nd gear shift and they do not show any throttle being pulled, the reason, there was no lack of traction.

You do make an interesting point, I wonder what the log looks like when the limiter is hit.