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Has anyone done any traction control tuning to aid in acceleration?
Like the racelogic system does??? Only that since you have an ETC you can tune the ETC or something similar to allow you a specified amount of wheel spin?
I don't expect it to be accurate in the way of adding x% of slip, but you could tune it to achieve the best acceleration possible...
Done it?/
Thanks
I have the TC system stillenabled on my E38 and it works somewhat like that. I get some spin in the dry without it activaying, biut if it's wet and she really lets go, it comes in gently, well much better than stock. Is that what you ar getting at?
I am trying to see if at all can be done. Because the BCM is what controls the active handling and part of the traction control. I would love to be able to "modulate" the throttle or control how much it modulates vs wheelspin or something similar. Not sure how it all works and if maximum torque plays a role in this.
Not the BCM... but the EBCM.
What did you do to tune it?
I tweaked the commanded torque settings to allow more than STD. when TC kicks in. It also ramps in slower. If I give it a bot full on a corner, the back will step out a bit and you can "right foot steer" the car a bit, but only if it doesn't end up in full on spin. Once it goes too far, the TC system kicks right in and drops the power, like chirping 2nd gear etc. Otherwise it just limits the power to just over the current traction level. I'll see if I can get the tables I played with. I'm at the AusCERT conference ATM so will fit it in when I can.
Simon
Simon did you come up with your bits a pieces yet... Have been looking at this myself....
Sorry, I was AusCERT last week in the Gold Coast (For you USA guys, think of driving from New York to Miami for an IT security conference, then have Miami get 12 months of rain in one day........)
So, back to the TC settings.
I altered B2517 "TCS Throttle Limiter by Input Speed" increasing the stock numbers for the RPM ranges in each gear. The method used was to slowly increase the settings till I got "minimal slip" on a dry pavement. So if I was say, doing a left of right turn on a dry road and went WOT, I'd get some over-steer, but no wild smoke show. Then if the road was wet and she really let go, TC kicked in hard and stopped it all.
I think I also altered B2501, B2502 and B2503, B2504. All were taken up a bit
The result is that if the TC switch is not touched at all, you can launch hard with minimal wheel spin and even get some slippage through peak torque with out the TCS system kicking in. But if you light up "big time", TCS kicks in and drops engine power. I'll see if I can get some logs tonight with TCS on and off.
Simon.
I know that feeling.. I did the Perth to Port Douglas trip via road last year for the M$ APC.. What a journey.. But something you need to do at least once in your life and I had that much fun I will probably do it more often...
Anyways thanks for your input Simon... I just need to appy this to 0411 now...Gives me a great filler on the weekend, 3 days of fun coming up... Just gotta find some back of nowhere for testing... The blue meanies are oh so quick to chuck your ride on the back of tilt tray these days....
The good part of testing this, is that you actually want to stop the spin. So I'd be looking for a more slippery surface than normal for the initial testing. Perhaps a good dirt road where some initial "slip" would be expected, or just a gravel car park / work lot would be fine.
- Try the stock settings on the gravel / dirt and note how hard the TC kicks in.
- Dull the setting down progressively to gauge how they are impacting the torque delivery on the "less than favorable" ground.
- Once you get it close, then move to the a paved road, perhaps a concrete loading area or long driveway would be a great place to test if available. This will keep the boys in blue away.
Remember that the biggest impact of this tuning will be in 1st and maybe 2nd gear, so you can actually do full testing without breaking the speed limit. Taking off "hard" out on the open road when no other cars are around would be hard to justify as "hooning", you are just getting up to speed quickly.....
So looking forward to giving it a go... No just the spot to get this up to scratch... :)
BTW.. They Anti Hoon Legislation here in WA has a couple of tricks up its sleeve.. "Testing a vehicles performance on a public road" "Undue and Excessive acceleration".. Seriously what has the world come to... :doh2:
I still fail to see the input speed... and I am still wondering how does the electronic throttle control kicks in... I wish there was a way to control the ETC a bit more.
Well, no logs this evening. It rained so there wasn't too much use.
Highlander, what "input speed" are you talking about?
I'm using an E38 controller so the tables are probably different if you are using a different controller.
This is the goal
http://www.youtube.com/watch?v=y1zrJq6u7vc
how did you get on with this in the end?Quote:
Originally Posted by Highlander
Well... Never got around to testing this. There are a couple of parameters I changed, but I seemed to still have too much interference. As soon as I have my car back I will test it with road runner.
I'd forgotten all about this thread. Here's some info I posted over at http://www.ls1.com.au
Well, it's been raining here so I did some testing in a wet concrete carpark ( no, not the local shopping center ). This shows what my current TC settings will do wen there is "significant" loss of traction.
http://farm3.static.flickr.com/2714/...51658b19_o.jpg
So, we have....
- Yellow: Shows RPM
- Cyan: Electronic Throttle Control Throttle Position, the actual blade position
- Green: Accelerator Pedal Position, the actual pedal position
- Purple: Vehicle Speed Sensor
So what is happening.....
- initially, ETCTP is at the idle level of about 9% and the APP is at 0%. VSS is also 0.
- From habit, I blip the throttle to raise the RPM ready to take off. Manual drivers of older modified cars will understand this......
- Clutch is released and and throttle is fed in quickly. Note that ETCTP and APP follow each other closely.
- the car starts to move and quickly breaks traction, VSS rises rapidly, as does RPM.
- At about 30kmh wheel speed ( thge car was possible doing 10kmh ) the ECM starts pulling ETCTP opening and quickly reduces it to about 30%
- The rate of VSS increase drops rapidly.
- VSS drops from a peak of about 40kmh, to actual vehicle speed of about 20kmh.
- As VSS approaches actual vehicle speed, the ECM commands ETCTP back up to the pedal position.
- This causes a break in traction again, and as VSS passes a set threshold, the ECM drops ETCTP again to control the spin.
All this occurred in 2.5 seconds and while there was spin and TC reduced power, forward motion was not impeded that much. Remember that this was on soaked concrete, about as bad a surface as you can expect. Sure you may get a section of road covered in diesel and water, or covered in thick ice, but not much is going to help you on that.
Simon.
what are those settings? care to post a file?
The basic settings are.....
- All torque reduction control setting are set to off, except for B0517
- B0517: TCS Torque Reduction By Thrttle Option - is set to Yes.
- B2501: TCS Maximum Engine Torque - is set to a value over the expected peak torque. In mine it's 700 Nm
- B2502: TCS Minimum Engine Torque - is set to the least amount of torque wanted. Mine is set to 80 Nm
- B2503: Delivered Torque Upper Duty Cycle - set hi, 90% for me.
- B2504: Delivered Torque Lower Duty Cycle - set medium, 35% for me. I think this helps set the control of the torque delivery when TCS is active.
- B2514: TCS Throttle Limiter By Gear - All maxed out.
- B2517: TCS Throttle Limiter By Input Speed -This is where it all happens. Set torque limits for each gear and RPM to suit the traction expected. The real work is done in 1st and 2nd gear. Here are my settings....
1st Gear3rd and 4th are just higher settings again.
- 147.625000
- 157.500000
- 168.500000
- 183.250000
- 220.000000
- 273.500000
- 325.625000
- 399.375000
- 700.000000
2nd Gear
- 162.750000
- 173.875000
- 189.875000
- 215.250000
- 258.125000
- 314.875000
- 388.375000
- 480.500000
- 700.000000
- B2522:Torque Reduction Max - I have this set to 100 Nm
Now, with these settings and TCS turned on ( I.E. I haven't turned it off ) taking off hard on good dry bitumen has virtually no "detectable" wheel spin when sitting in the drivers seat. You can also feel the torque management release as you go through 3000 RPM. If you check the log data though, you can see around 5 to 10 kmh of wheel spin. So there is plenty of power getting to the rear wheels, just not enough to really light up the tires.
Simon.
These settings seemed to liven up my car.Quote:
Originally Posted by swingtan
thanks for the post, missed the reply for some reason! Will give it a try.
could any body translate the following parameters for me :
B6606 ETC TCS Exit Rate
B6609 Tip-In Torque Reduction
B6610 Tip-In Torque Reduction Min Speed
and what is the difference between B6603 TCS Spark Retard and B6604 TCS Spark Retard Fast ??
any help will be appreciated
thanks in advance
What do you mean by "Translate"?
When looking at any parameter, there is a "description" field in the top left of the screen that explains what the parameter does. Is this what you wanted?
Simon
I read the description but still did not under stand what is the purpose of those parameters.
i hope if you could help me
TCS exit rate = the rate at which retard is ramped out.
Tip In = the motion of the throttle opening up.
Retard Fast is used initially before switching to plain Retard.
The descriptions are not always intuitive... sometimes you have to read a description in conjunction with the neighbouring tables.
OK, how's this......
- B6606 - ETC TCS Exit Rate: Once the traction control system (TCS) is no longer needed, the system will ramp out the TCS retard by this amount every 12.5ms.
This might be slightly confusing as the PID mentions Electronic Throttle Control ( ETC ) but the parameters are in "spark timing degrees". I haven't tested this one personally, but there are 2 possibilities.
- The parameter reduces the TCS spark timing retard by the amount entered every 12.5mS until the retard amount = 0'
- The parameter reduces the TCS "throttle blade angle torque reduction" by this amount every 12.5mS until the reduction amount = 0
My initial thought is that the reference to ETC might be misleading and the value actually works on spark timing. It shouldn't be too had to check this though- B6609 - Tip-In Torque Reduction: Used to limit torque increase with throttle tip-in.
Basically, this will try to drop engine torque as the throttle is opening. It sounds like a "preemptive" action to reduce the possibility of traction loss by slowing the engine power ramp up. The value being set in a "torque" value indicates either...
- A "reduction amount". I.E. the PCM will try and reduce engine torque by this amount at throttle tip in and possibly references B6605.
- An absolute torque peak figure and would behave like B6611.
I don't know for sure though my feeling is the later.- B6610 - Tip-In Torque Reduction Min Speed: Minimum vehicle speed to allow the throttle tip-in torque reduction function to become active.
Pretty much what it says, below this speed, B6609 makes no difference. Above this speed it makes a difference. Most probably "tip-in" torque reduction was meant to be used as a "gear box / diff / axle saver" in manual cars.
As for B6603 and B6604, the descriptions are pretty good for these. B6604 is used when TCS first becomes active to give an initial torque reduction amount. If the TCS remain active ( wheels still spinning ) then the PCM wil transition to B6603 for TCS control. What this allows for is either...
- An initial big hit of torque management to stop wheel spin, followed by a lesser amount. For example, if you wanted to keep the power going, the TCS system would initially try and stop spin with a big hit to timing, but if you kept the foot down the TCS system would "back off" and allow more power through. This would be good if you tuned it well and wanted some sort of 'launch control", but would allow you to manually lift off the throttle if you hit a slippery spot.
- Start of with only a small amount of TCS torque reduction, and if traction loss remained, ramp up the torque reduction to stop all spin. This would be great for very slippery conditions or where the driver skill or knowledge of the car is limited.
Just remember, I've mainly worked on the E38, so some of my comments might be a little off....
Simon.
What a brilliant little modification!
Was at an (uphill!) run tonight at a makeshift sprint course on an old RAF base.
Traction Control was modified as above and kept on at all times, very minimal spin and no noticable interferance in the car (it lit up the TC warning), it is clearly cutting in but not as far as the driver is aware
2 rather crap runs mind...
http://www.youtube.com/watch?v=2G8MsKbPEWI&fmt=22
Good work Stigmund, did you log the runs? I found the best acceleration was achieved when I was getting some constant slippage while ramping up through the gears. It's a good idea to do a few runs with TC both on and off to compare the ramp rate. Then you can see where additional tuning might help.
Simon.
no didnt log tonight but we have a proper strip night coming up. To make life simple can you list the pids you logged with as I am currently using a specific set.Quote:
Originally Posted by swingtan
I used your 1st and 2nd gear settings then for 3rd copied 2nd and added 15 to each cell, then copied 3rd to 4th and add 15 etc
For the TC tuning, I just look at....
- RPM
- VSS
- ETC-TP
- APP
- SparkAdv
The 2 throttle PID's help to show when TC is active, as does the commanded spark compared to the high spark table in the tune.
Then I compare the shape of the RPM and VSS lines between runs to see the effects on acceleration. Obviously, steeper lines in the graph mean faster acceleration.
Simon.
I did not find those parameters in my .tun file is my operating system different ? i have a LS1 Lumina SS coupe (GTO)Quote:
Originally Posted by swingtan
That would be because those settings are for the E38 controller, not the LS1.Quote:
Originally Posted by wesam
Simon.
I don't suppose some clever bod has produced a set of numbers for B66** numbers (LS1) cotrollers as a jumping off point and would be prepared to share. It would be greatly appreciated.
Well..
I have my road runner installed. I will be tuning this a bit in my car these coming days. I am going to strap my car down on the dyno and test and Tune b1902 FIRST. After that it's more or less b6612 to have a complete control of what torque output you get. I believe that once you set both of those tables on the LS1, the rest should come quite easily.
Retarding 9 degrees on a cammed car are going to yield a torque loss far greater than 3% as on the STOCK calibration.
Pulling this from a deadQuote:
Originally Posted by Highlander
Did you tried this on dyno ?
Do you think its linear relationship between timing and torque so 16 degrees of timing will make 6% torque loss ?
My VZ would practically stop when the TC cut in, so I decided any change was probably better.
As a first step I simply reduced B6603 TCS Spark Retard by 50% and the result was great. No wheel spin, but the torque drop
when TC cut in was way less. It needs more work but for one change the results are amazing.
Cheers Steve
The problem is that when you really want it which is on the WET... torque needs to be cut even more or you will get wheelspin and dangerous situations.
Yep been taking 50% out for years now. It's a good number and allows the driver to actually control a slip rather than take away all powerQuote:
Originally Posted by vzsv8