Lets test and discuss torque coefficients..

[Higgs Boson]

and on top of that, Spark Airmass and all the other Airmass tables.....very little info out there about these.

[realcanuk]

My torque pid maxes out at 640.. so impossible to get actual numbers. I am sure it would be easier to accurately tune this stuff with data.

[GHuggins]

So true to both statements. Correct data is everything in this and the diagnostic world...

[Higgs Boson]

yes, 2.25 full functionality has me in great anticipation.

[GHuggins]

OK, so I got through tuning another 13 ZL1 with a manual 6 speed today and thought since it was a manual trans car I would give the torque coefficient MAP A,B,C,D tables a try on it. This is what I saw or experianced... To begin with I did the usual and dialed in the MAF and O2 placements to get my fueling right -(.9 on proportional and 1.25 on integrator for anyone wondering on this one), dialed in spark how I wanted it and then dialed in or more or less increased the Torque Tables. With this setup I was running a constant 11.9 to 12.0 A/F ratio through the pull and put down a best 586hp to the rear wheels. Well at this point I figured, what the heck I would give it a try. SO I multiplied my coefficient tables by 1.04 "I think that was it atleast" and first thing I immediately noticed is my WOT fueling is pretty bad off. You know how the factory WOT PE will command right at 11 AF right around 5500 then continue with that till the end, well all of a sudden my fueling went back to doing this right around 5500 and running a touch ".5" leaner in the lower rpms even though I had already dialed in MAF and SD? I also noticed in my datalog that delivered torque increased even though it didn't show any gains on the dyno at this time. Instead of knocking my airmass tables back down I went ahead and redialed in my MAF curve to where I was back to running an air fuel of 12 (give or take .1). Now I'm putting down a best hp of 590 to 595 and torque of 545ish to the rear wheels. Really think this is just coincidence and possibly it was just a different moisture or cooler incoming air into the dyno room since it did rain pretty hard about 20 to 30 minutes prior, but never the less did find it interresting? AND really not bad considering it's only got a K&N CAI and KOOKS long tubes installed. Put down 530 stock, so a 60hp gain? I did put down 604 once, but I don't count the little fuel cut spike at the end / LOL.... Don't know, I'm going to do one final check and the last 3 pulls on it in the morning before pulling it off and doing my final test drive and clean up. Guess I'll see what it does then if anything for it...

[GHuggins]

Oh also would like to praise which ever person came up with the VE table for 2.25. Really like being able to set the MAP and RPM scales however you please.... As long as there aren't any glitches

[Higgs Boson]

Did you monitor your delivered timing between both tests? I have seen spark timing increase over commanded to achieve a higher torque level so it might have bumped up 1 or 2 degrees and put down a little more power.

[GHuggins]

Didn't look at that or atleast didn't pay attention to it and I already saved over that dyno pull, so I can't look at it now. Just did 3 more pulls this morning to verify fueling after sitting over night. PE still doing 12 +/- 1 and still putting down 590 to 595 to the rear wheels on all three pulls. Peak torque came up a little into the 550's. Believe that was because of the 6 degree cooler temp coming in the dyno room. Otherwise very consistent even with a hot motor. Still don't think the airmass tables had anything to do with it, but who really knows other than the engineers that set it up Now I just have to drive it and make sure driveability is spot on which considering what was done, should be.

[GHuggins]

Higgs it dawned on me that even though I did not save my "test" log, I did atleast have my final dyno log to compare to my tune. I always try to atleast save the final dyno and drive log incase it comes back with things different later. SO I went back and watched it closely... It would seem that after changing the airmass tables, that even though I was pretty sure I took out a lot of the ability for the ecm to alter timing, that it did indeed add up to 2 degrees of timing through the pull and here I thought I was adding more than enough to it already? It also changed delivered torque to a number "higher" than what the dyno was reporting? It added roughly 15 to 20 lbft of torqe to what it actually put down. All though if you do the math this is still lower than what the engine itself was actually making...

So does this mean that these tables do alter more than just trans response? It did change WOT fueling and it did "alter" what kind of timing the motor used... Although on the newer ECM's I don't remember it altering either one of these, but I also didn't have a scanner to watch timing or delivered torque since it was on the 15 escalade I was discussing with you.

Again, just speculating since I don't know or thoroughly understand what it is that these tables actually do other than "make" the ecm "understand" better what it's putting or atleast tying to put down to the ground or I guess "flywheel" in this case?

[Higgs Boson]

I think we know about the same amount on this now.... :-)

The Peak Torque table is quite a bit higher than what is advertised by GM, the driver demand table is higher than advertised, etc. so the numbers don't match up with actual power/torque. There is a lot to learn here.

[GHuggins]

So I guess here's the real question... Do we manipulate tables like these to use to our advantage or just try to dial them in correctly?

I also only thought that Ford was the only one out there that would add timing on it's own to try and meet the torque request. Didn't really dawn on me that anything using torque based setups would do this. Really just thought it was a Ford thing since up until now I hadn't really seen or atleast paid attention to it. I know on Fords the whole idea is to dial them in correctly so the ecm isn't "struggling" with itself. This also will make long strides toward getting driveability better than OE, but I just saw the benefits of this being slightly higher on a GM platform. Driveability was perfect. Fuel trims at or near 0 longterms. Absolutely no spark knock. Customer was really happy with the all around "betternesss" of it. I even noticed the throttle hang that most ZL1's have when your doing light throttle low rpm shifts was pretty much gone. Coincidence? Don't know.

Seems like just when we think we understand something, a curveball gets thrown into the equation

[lt1z350]

Know this is an old thread but since then have any of you learned more on these tables? Reason I ask is I am doing my 2016 Cadillac CTS vsport and one major issue is no tcm support to date. So two things the stock not very firm shifts and a brick wall when it hits the tcm torque management max. At that point it will just close the throttle to keep boost and peak torque down. To help with the shifts I though the only thing to do was raise the minimum timing at wot so that it wouldn't drop to -20 on the shifts and that did firm them up quite a bit at wot. Now I see this and how it helped on the a8 with forming shifts. I would guess raising the boost from 10-12 to 16-18 will add 50-70 hp to it so adding to the whole table the percent gained is how you achieve the firmer shifts?
Second big question. If anyone has figured out that these tables to manipulate what the ecm/tcm is seeing for max torque is it possible to use these tables to trick the tcm into seeing less torque? That way I don't hit that wall so quick on the tcm limiting power. Or might just pull to much from the trans and make it slip rather then have the bieat possible shift with the most power the tcm will allow. Just cannot find really anyone that has played much with this car. I have applied some of what I read on the atsv but that too doesn't have much info from anyone on the forum. Seems only a small group of people have even talked about these tables so only a small group are trying to achieve the perfect tune. If I had any of you near me I would just bring the car to you but being in north Florida I am limited to trying to learn it my self but only off what guys like on here are willing to share. People like me that read do appreciate it. as much as I post about the vsport in v6 area I can't get answers on much at all so spend more time reading from the v8 side then try to apply it to the turbo car