THROTTLE BODY IS CLOSING E39A Buick Verano T(urbo)

Boost,

I've kinda followed along with your development of the Turbo Buick and appreciate all the information that you have shared. Since you have pretty much zeroed in that the throttle closing is a form of protection which is most likely due to the predicted torque value ..... about the only thing I can offer up is what some of the old hacks used to have to do.

For the old LT1's (opti spark, not DI engines), we didn't have any COS's or any 2 bar, 3 bar stuff to play with. One of the work-arounds was to 1/2 all the tables so that you could use a 2 bar MAP (there is more to it, but that's the jist of it). One of the other things that you had to do was divide the displacement of the engine by 2. My guess is that if you went through all of this (there are quite a few tables that you would have to play), the "predicted engine output" should also go down. With the ECM's (ECM and TCM) seeing the lower predicted torque .... that hopefully should limit the amount of throttle closing you are getting.

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Originally Posted by turbo_bu

Boost,

I've kinda followed along with your development of the Turbo Buick and appreciate all the information that you have shared. Since you have pretty much zeroed in that the throttle closing is a form of protection which is most likely due to the predicted torque value ..... about the only thing I can offer up is what some of the old hacks used to have to do.

For the old LT1's (opti spark, not DI engines), we didn't have any COS's or any 2 bar, 3 bar stuff to play with. One of the work-arounds was to 1/2 all the tables so that you could use a 2 bar MAP (there is more to it, but that's the jist of it). One of the other things that you had to do was divide the displacement of the engine by 2. My guess is that if you went through all of this (there are quite a few tables that you would have to play), the "predicted engine output" should also go down. With the ECM's (ECM and TCM) seeing the lower predicted torque .... that hopefully should limit the amount of throttle closing you are getting.

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Thanks a lot turbo_bu! Actually, my recent findings indicate that the throttle closes for two different "symptoms", though it may all boil down to the same culprit anyway. To be quiet frank. I am VERY frustrated with this. I can't get anywhere. I am well aware of who else are tuning and racing these and also whether they have overcome this hurdle and what means they used, or if they haven't and their results are mediocre. I know there are several silent followers, but I just want to race and WIN and need help.

That being said the biggest "closer" of the throttle to 40% and keeping it there when it's least desirable is DESIRED BOOST - or rather, the difference between it and ACTUAL BOOST. I have produced a specific data log on purpose to show this and will post it sometime tonight. I am still producing 320 lb-ft torque with the "throat pinched" and the car wins street races but the whole thing is pointless and quite pathetic.

I have tried lowering the boost to match desired, and this is worthless as it wants 15 psi and that is not enough for even 300 wheel horsepower - the car runs no harder than stock and will never hit 8s, despite the smooth pull with no throttle closing whatsoever.

I have also tried somehow making DESIRED BOOST higher, this would allow 26++ psi with the throttle open an produce 350 wheel horsepower and run mid 8s. It is not possible for me to control this. It moves up and down as it pleases and routinely drops like a brick from 43 PSI (including baro) to 30 PSI, within a couple of RPM (!!) and shutting down the race.

As I understand from the description P.I.D. control is only during closed loop, I still tried it and all it does in any direction is create ghost cams and stalling / backfiring.

I am stuck in between and what makes it terrible is the tease of when it does open up for a few seconds it wants to scrape the rear bumper and rip the tires off the wheels.

Perhaps a huge turbo that can live at 14-15 psi or external software can turn this train wreck around... sucks a metric f-ton. (in the words of a friend)

Boost, remember what I said in my PM a month or so ago...same still applies Im afraid. Be a cheaper fix than pulling your hair out all the time.

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Originally Posted by turbo_bu

Boost,

I've kinda followed along with your development of the Turbo Buick and appreciate all the information that you have shared. Since you have pretty much zeroed in that the throttle closing is a form of protection which is most likely due to the predicted torque value ..... about the only thing I can offer up is what some of the old hacks used to have to do.

For the old LT1's (opti spark, not DI engines), we didn't have any COS's or any 2 bar, 3 bar stuff to play with. One of the work-arounds was to 1/2 all the tables so that you could use a 2 bar MAP (there is more to it, but that's the jist of it). One of the other things that you had to do was divide the displacement of the engine by 2. My guess is that if you went through all of this (there are quite a few tables that you would have to play), the "predicted engine output" should also go down. With the ECM's (ECM and TCM) seeing the lower predicted torque .... that hopefully should limit the amount of throttle closing you are getting.

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I remember these tricks and was the only way to accomplish boost with a PCM/OS that was never designed for boost.

But there's always been limitations on the LT1 PCM even without boost and just engine mods like cam, or even long tube headers with parameters missing that caused the dreaded "Split BLMs!" along with many others. And we found tricks to tune around them.

Here it is 2014 and we've finally cracked them and changed LT1 tuning for modified engines and transplants! (Still no boost)

So it can be done properly and Boost has spent major amounts of time modding a basically stock 2013 engine to extremes with what's left on the table. It's time for EFI Live to step up and find this limitation in tuning and with it being a new MY there's still a chance they will find the time to do so. This vehicle is soon to become a popular tuner car for a long time! :grd:

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Originally Posted by ScarabEpic22

Boost, remember what I said in my PM a month or so ago...same still applies Im afraid. Be a cheaper fix than pulling your hair out all the time.

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Thank you Erik! I know and I seriously was ready to do anything it takes, and definitely still may go that route. Whatever it takes. However, since I discovered that the actual "higher than stock torque at a specific RPM while boost is still low" was closing the throttle only a small amount and not as often as the huge snapping shut 2-3-4 times per gear as soon as Desired Boost drops and Actual Boost overshoots it. This encouraged me to work within EFILive to find out how I can bring this completely under control before I complain about the transmission. However, I have tried every single setting and strategy and there are simply things missing. If anyone EVER is to get a 2011-14 Regal T, Regal GS, or Verano T running close to right, we must ask and patiently wait for more tables to control the Throttle Tragedy.

I know from correspondence with one of the only other guys on the planet who is racing a Verano T and using a competitor's product (and also is keeping tabs on this thread) that they had serious problems with both the automatic transmission holding back torque as well as the throttle shutting on the dyno. However the software's ability was revisited and the problem solved.

I love EFILive so much that I would rather get it running as good and as precisely dialed in as possible with what's available. But I really really hope that we can work something out, I'd be willing to submit as many data logs as possible and thrash the car until the transmission is soup and the tires are goo.

EagleMark, I really appreciate what you are saying! I do however realize that despite my very good relationship and friendship with EFILive, the car may simply not be a priority due to it's rareness and tons of other way bigger projects. I am in communication with Opel racers from Russia (who are also following this) and not many worldwide are tuning the LHU well with EFILive. The Holden / Vauxhall / Opel / ect versions of the Astra J OPC or whatnot are hot tuner cars but still are rare and underdogs to the Ford and VAG crowd. I think the Saab also has an LHU.

The LNF was a big hit with the HPT crowd and I don't mind that EFIlive stayed away. The new platforms are much more sophisticated and elegant. And the LTG tuning is going well, I am kicking serious ass tuning ATSs and have some dreams / aspirations about a possible future Malibu T.

But I will be owning and racing this for a while. So thank you for your kindness and support, but all I can do is try and whine, and try not to tick off my dear friends too much.

I also FULLY realize that I am not exactly God's gift to the tuning world and am probably overlooking a whole bunch of basics, but I am working on it!!!

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Originally Posted by Boost

I have produced a specific data log on purpose to show this and will post it sometime tonight.

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The first log file attached named LOKURA is purposely overboosted and barely driveable. It was done to show and exaggerate what is occuring.

The second log (Tune J) is one of my fastest dailys. It shuts the throttle quite nicely, and barely makes 300 torque. But if I add boost it shuts the throttle more and goes slower, and if I lower boost it shuts the throttle less and goes slower. Thanks for looking! (Calling Brian and Rhino!!!)

Boost,

Thanks for sharing all of your hard work. I hate to beat on the band-aid methods too much since they shouldn't be needed, but since it sounds like your dealing with a boost controller fighting you. Can you limit the boost signal going into the ECM? Basically preventing the MAP sensor from showing anything larger than say 15 psi? I haven't looked at the output of the MAP sensor, but my hunch would be to modify the resistance so that it never showed anything that was higher than ~15 psi.

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Originally Posted by EagleMark

It's time for EFI Live to step up and find this limitation in tuning

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Time, ah, time being the enemy here :Eyecrazy:
From what I understand the cars running the E39 & E78 seem to be ok, it's when they went to the E39A we've struck the boost issues? It might also be that they've put more tables in the 2013+ software, I don't know, I honestly haven't spent hours and hours on the these ECM's in the last 6 months or so and because they are relatively new GM are having a field day with release changes.

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Originally Posted by Boost

I know from correspondence with one of the only other guys on the planet who is racing a Verano T and using a competitor's product (and also is keeping tabs on this thread) that they had serious problems with both the automatic transmission holding back torque as well as the throttle shutting on the dyno. However the software's ability was revisited and the problem solved.

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Guys I don't like to beat about the bush (that might be a local expression!), I don't want to tell anyone to use other tuning software, but you can only wait so long right? Don't be under the illusion that EFILive is working on this issue 100% of the time, we aren't, our project backlog is huge and we have new projects on the horizon we need to keep the ball rolling on, but at the same time we are trying to be mindful of these on going problems.

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Originally Posted by Boost

The car may simply not be a priority due to it's rareness and tons of other way bigger projects.

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That is something we need to balance out and will never keep everyone happy.

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Originally Posted by Boost

But I will be owning and racing this for a while. So thank you for your kindness and support, but all I can do is try and whine, and try not to tick off my dear friends too much.

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Never Roland, you are handling yourself very well :wavetowel2:

Thanks for saying so Ross, we are on the same page! Just a note - the ATS 2.0T also has an E39A and I have zero issues with throttle or boost when tuning those. Since I have access to their T43s, I can see that the trans. is permitting up to around 400 lb-ft (surely not the case with my 258 lb-ft rated unit) and can also turn off various TM settings from there.

It may be that since they went with a Mitsu turbo and it's newer they found better ways to manage boost also there. I am particularly impressed with the low RPM initial spool with the Caddy. The LHU as we know sleeps until 3k, then fury.

With patience and continued experimentation we will get there - if I have to infuse another product and just use it as a whore for the tranny - so be it. :)

I surely hope though that at least 1-2 additional power controls are released for these with each major update... ;)

You guys rock (and Stock is Cock! <<< popular TORQUE SOUTH sticker from 2006 era)

;)