C8 Turbo Torque Limits

[jacep]

I have a maximum engine torque limit that I am missing somewhere. Does anyone know how or what I need to change to get around this? Check my log channel "maximum engine torque" it seams to be limited to around 390lbf. The only way I have gotten around it in the past is a piggyback standalone for fuel and an analogue out going to the stock ecu that never allows the ECM to see boost pressure. I am trying to tune this all native as the piggyback was creating its own set of problems. Any incite would be greatly appreciated. Thanks

[GHuggins]

It may not be displaying right in the log. Nothing shows it's being limited via timing or throttle. Fuel needs A LOT of work. Usually max engine torque refers to well the max engine torque table which is twice to three times what it's showing in the log so I have to lean towards it not being displayed right in the scanner.

[jacep]

It may not be displaying right in the log. Nothing shows it's being limited via timing or throttle. Fuel needs A LOT of work. Usually max engine torque refers to well the max engine torque table which is twice to three times what it's showing in the log so I have to lean towards it not being displayed right in the scanner.

Thanks for the info, I'll keep messing with it. Its extremely slow right now and I'm not seeing whats holding be back

[veeefour]

Was able to fix the same problem with our latest C8 twin turbo build, was having issues with TB closing and other stuff.
Car picked up 200hp with just 5psi going from 9s on 60-130 to 6s range. Runs like stock:

https://youtu.be/_xUA1KtXwk4?si=pTIgFovgMxGFEMOb

[GHuggins]

So something in the background or overlooked then?

[GrannySShifting]

You gonna tellm what it was or? LOL

[veeefour]

So something in the background or overlooked then?

Plp say its similar to Camaro but id say very different: widebands, neural network...had to change few more things.

[GHuggins]

Plp say its similar to Camaro but id say very different: widebands, neural network...had to change few more things.

OK, I follow now. You just dialed in the NN, torque models and so on so it better knew what was going on. I already do all of that, so I guess I'm good there

Thank you for clarifying.

[veeefour]

OK, I follow now. You just dialed in the NN, torque models and so on so it better knew what was going on. I already do all of that, so I guess I'm good there

Thank you for clarifying.

nope

[GHuggins]

nope

OK, guess i don't follow then.

[TriPinTaZ]

So much info in this thread. Love it.

[jacep]

Was able to fix the same problem with our latest C8 twin turbo build, was having issues with TB closing and other stuff.
Car picked up 200hp with just 5psi going from 9s on 60-130 to 6s range. Runs like stock:

https://youtu.be/_xUA1KtXwk4?si=pTIgFovgMxGFEMOb

Very impressive!!! I have a lot of learning to do lol

[GrannySShifting]

So much info in this thread. Love it.

The library at Alexandria didnt have this much knowledge in it

[veeefour]

The library at Alexandria didnt have this much knowledge in it

I went to Alexander the Great to ask about C8 tuning problems I had...he said:
-boy, do it yourself cuz nobody knows...

...now I know...and there is a way for you to know but it aint here.

[jacep]

I finally got some time to play around a little more and I'm still lost lol. Changes in this log/tune are no aux fueling, non filtered map sensor, non filtered MAF, and max pressure limits on Neural network (VE Y axis) raised to 1.3. I did 2 pulls one with boost control set to 130 kpa the 2nd set to 145kpa. STFT are way out of wack, curses' and drives at low APP good, but extremely slow under boost. Throttle closure is at about 45-50%. (full throttle reads 84% on my logs). With the standalone filtering Map and Maf and 50% throttle closure the car would still run really hard.

Does GM currently have any boosted production cars that run the Neural Network?

Log V6 is Aux fueling, filtered Map, Filtered Maf, 160 KPA boost (notice the time spent in each gear)

What would you guys recommend attempting next?

[jacep]

Here is a log of a stock car. Notice the Max Engine Torque and Engine Torque are almost identical. In my boosted logs they are completely different. Any idea what these are actually logging?

[GrannySShifting]

I went to Alexander the Great to ask about C8 tuning problems I had...he said:
-boy, do it yourself cuz nobody knows...

...now I know...and there is a way for you to know but it aint here.

Well how did you become to know, and how do you recommend the guy here comes to know would be the ?

[GHuggins]

Just a general question here to the OP. Did you try changing your Load values for the NN to read into boost? In other words change them to something like 2 instead of 1's?

Adding boost to NN equipped vehicles normally isn't that hard to do. It relies heavily on having the injector tables right and having the density table dialed in. I haven't done one running that much boost yet. Just pushing 12 psi. I imagine at that point you might need to scale the injectors a little to keep the MAF.

Otherwise, I get the feeling VeeeFour might reply if you pm him.

[04silverado6.0]

Love it when im having an issue and someone brags knowing the "secret" without telling. What a real hero.

[jacep]

Just a general question here to the OP. Did you try changing your Load values for the NN to read into boost? In other words change them to something like 2 instead of 1's?

Adding boost to NN equipped vehicles normally isn't that hard to do. It relies heavily on having the injector tables right and having the density table dialed in. I haven't done one running that much boost yet. Just pushing 12 psi. I imagine at that point you might need to scale the injectors a little to keep the MAF.

Otherwise, I get the feeling VeeeFour might reply if you pm him.

Hi Greg Thank you for the info. I have upped the NN inner load from 1 to 1.3 I'll go back and try 2 for both the inner and outer layer max load.

When you refer to density tables are you talking about the "density multiplier" under fuel-general-injector flow rate?

What are your thoughts on lowering peak values on the Virtual torque tables?