what parameters control Max Engine Torque values?

[ayousef]

Airmass A,B,C,D Tables
Max Torque Timing Table
these are known to alter Delivered Torque

I've gotten to the point where I just get all the torque based tables as close to what the combination is really making and then just verify it isn't pulling spark or closing throttle and A/F is correct. After that, how could it be limiting power?

You just seemed to have mentioned the Airmass torque coefficient tables, how about the RPM, Spark, MAP coefficients? Does any table alter torque calculations without changing "delivered torque" in the process?

[Higgs Boson]

have you tried the max torque timing table already? set it to 3 or so degrees higher than your Hi Octane table in all the cells...it's tedious.

[reubone]

looking for this very thing to keep delivered tq up when nitrous is engaged

[Ben Charles]

Figured something out by accident on the Max Engine Tq PID. It is directly referenced from the GMVE table even if you have SD disabled in the tune.

[Higgs Boson]

Figured something out by accident on the Max Engine Tq PID. It is directly referenced from the GMVE table even if you have SD disabled in the tune.

That explains why it doesn't match up with the Peak Torque Table. So now then, what are we all doing with the Peak Torque Table? Has anyone found more than just PE fueling that could reference it? Are most maxing it out? I have been trying to model actual peak torque for each car and not go too high.

[Higgs Boson]

Figured something out by accident on the Max Engine Tq PID. It is directly referenced from the GMVE table even if you have SD disabled in the tune.

I'm going to go out on a limb here and say that Max Engine TQ does NOT have to exceed Predicted Engine TQ (otherwise it is limiting) as the E78 Guide states.

I DO believe that Predicted Engine Torque has to exceed (Delivered) Engine Torque (otherwise it is limiting).

I don't know what correlation you found between MaxET and GMVE, but my GMVE is properly tuned with wideband, and confirmed through trims, and Max Engine Torque is WAY lower than Predicted and Delivered (100-200).

Otherwise, I can't figure out how to raise Max Engine Torque, it just is what it is......unless it is referencing the highest GMVE value in the table and calculating back off that as a % to whatever cell you are in based on Peak Torque.....

Interesting. I think I will have a look, there are plenty of spots I don't touch in the VE table, I wonder how high the highest number is.....

[Higgs Boson]

I just calculated this:

My max value in the VE table is 11907 (not one I would ever hit as it is at 7000 and 1.72 PR

My max value in Peak Torque is 1374

My Max Engine Torque at 3250 RPM (full throttle) is 466 ft lbs.

My VE value at 3250 at approx 1.29 PR is 4093

11907 / 4093 = 2.9
1374 / 466 = 2.9

So now I want to see what happens when I edit the VE table to use no value higher than my actual max, rather than an arbitrary number like 11907...... To be continued.

[czipar27]

[QUOTE=Higgs Boson;397751]I just calculated this:

My max value in the VE table is 11907 (not one I would ever hit as it is at 7000 and 1.72 PR

My max value in Peak Torque is 1374

My Max Engine Torque at 3250 RPM (full throttle) is 466 ft lbs.

My VE value at 3250 at approx 1.29 PR is 4093

11907 / 4093 = 2.9
1374 / 466 = 2.9

So now I want to see what happens when I edit the VE table to use no value higher than my actual max, rather than an arbitrary number like 11907...... To be continued.[/

has anyone ever figured out what we can change to directly impact Max engine torque and nothing else? It seems like most all 2015 and newer trucks have this issue of Max engine torque being lower then commanded engine torque and they pull timing to achieve the correct torque value.

[lt1z350]

This is going to be a huge problem when they go to turbo stuff on v8. I see it on the 4 and 6 cylinder turbo stuff now. As soon as delivered torque goes over the max torque value it will drop the boost or close the throttle depending on if you have fast torque exit disabled or not. I have been playing with virtual torque editer but yet to get it to not cross. I haven’t tried playing with max torque tables yet but every time I have seen done by a big company on a camaro or ats 2.0t is doing this so I’m gonna step out on a limb and say no one has found a solution to it and just tunes up to it or limits the power. Most of these canned zzp rpm diablo tunes all just let the throttle close or boost go between 14-21 and the customer thinks it’s runing well as it does have spikes of decent torque. It’s no wonder most of the turbo swapped cars don’t run worth a shit none are tuned correctly. Higgs or Ben if you read this and know how to get max to increase please commmet or pm me. It’s making a lot of GM turbo stuff look bad honestly as these bad tunes are making all GM cars look pathetic compared to ecobooat anyway so I assume ford isn’t seeing such a problem. Those that tune for a living going to be in a world of hurt if isn’t figured out when GM drops all the overhead cam turbo stuff on us if they use the same logic. I just won’t lie to a customer and tell them the tune is right like many wi when I know I see boost and throttle issues even if that customer says the car “feels fast” as I know a lot more in it if this is corrected. Going to post up a log when get home to laptop so can see what I am talking about and no I haven’t touched the ve as when lol at it the GM version is such a mess I don’t know where to start and if even tried to smooth it looks to change drastically.

[Higgs Boson]

I personally own a 18 Raptor and 17 Z06. I have a whipple 2.9 coming in soon for the Z and that will give me more experimentation time with this issue since I can spend some time on it. most other cars I tune are bolt ons anyways I don't run into issues.

usually the issue I see with boosted NA applications is limitations from running out of fuel with the DI system, it appears the port kits solve most or all of these issues with closing throttle and killing boost.

As far as tuning the EB in the Raptor, it's the same situation, however with the GenII 3.5 having port and di combo helps a lot. The EB applications are "more fun" to tune as the ford ecm is a lot more advanced and you can really set things up how you can imagine them. The GM logic and architecture feels antiquated.

We just got the Gas Monkey Pantera with an Ecoboost traded in at my store and it wouldn't even start or run, I finally was able to write over the SCT tune with HPT and getting it going again, the car is really cool. :-)

[lt1z350]

this is miserable on the 2.0t stuff which is really getting popular. Here is a log if look at the boost you can see when it crosses over the max engine torque the throttle shuts boost falls then I assume it just starts holding the boost down. Thats on the screen shot pull.Others do just boost and keep throttle open with no dip. Near the end of the pull the delivered stays under the max for a few rpm then starts feeding boost back into it. I need to have him add more channels as I gave him my zl1 list to use but need to see dc boost commanded things like that too on the car. I know my zl1 is very slow to open the throttle but once gets open seems to stay there it will take a whole gear to do it and kills the 60 foot at the track as so slow to get to full boost. Im about to try a z06 driver demand table thats not rpm based like the older stuff all had and see if that helps at all.
You mentioned max torque tables is there a good way to set them for the best throttle response? I would play with all this today but raining here so couldnt even think about any full throttle stuff so going to do research and maybe put my big heat exchangers on my camaro and work with this ats more. I just wont lie to him and say its right because he says it feels faster then stock. There has got to be a way to get max over delivered and make it hold the boost well. Thank you for seeing this and answering and good luck with the new projects.
As for my zl1 doing a whipple or the new heartbreaker 2650 which ever I do will have port on it too a big investment so saving up.....LOL

[cesar]

Bumping this. I know it's super old but I want to know if max eng tq reference GMVE and is there a problem if immediate/predicted eng tq exceeds the max eng tq? Most trucks have the max eng tq being exceeded by the predicted tq

[Sneakyws6]

My 2017 Camaro SS that has a Procharger D1SC on it had issues with part throttle "surging". When I took it back to the shop to clean the tune up most of the changes were made to the variable cam timing maps. That made a world of difference in mine.

[lt1z350]

it depends on the platform how bad it will affect it. Turbo stuff it wont make boost as you command it others can close the throttle or limit the timing.

[cesar]

But what parameters control it? And how can people get away with tuning a gen V maf only and drive perfectly fine in and out of transients

[TriPinTaZ]

But what parameters control it? And how can people get away with tuning a gen V maf only and drive perfectly fine in and out of transients

Because they disable the VE calculation airflow and make it use Filtered MAF signal for all RPM ranges.

[cesar]

Now for the main question. What controls max eng tq parameter?

[lt1z350]

Virtual torque tables will raise the max torque but it will also bring up delivered torque. So will have to play with it to find a happy medium.

[TriPinTaZ]

Now for the main question. What controls max eng tq parameter?

Virtual torque tables will raise the max torque but it will also bring up delivered torque. So will have to play with it to find a happy medium.

^^ This. And then you have to raise the Peak Torque Table and mess with Driver Demand as well. Max Torque is also affected by Max Torque Timing.

[Ghostnotes]

Sub'd

Will be paying attention to this. Finally got my head wrapped around BIG CAM/NA tuning and have a V7 YSi coming.