Virtual Torque tables

[Jonblarc7]

If I have L86 cammed TSP 218/226. And it's been tuned on 93 runs great idles great.

Before the cam I previously enabled the E85 and added a sensor. I know the tuner didn't work on any E85 stuff and he did a great job and I needed it up a runing fast since it's my DD. I,ve been spending sometime getting the shifting dialed in. Now onto some of the E85 stuff.


When it has E85 in the tank my only complaint is. It's slightly jerky when coming to a stop at a red light. It's doesn't do it on straight 93.



Can I copy what he changed on the Virtual Torque>Airmass and MAP tables and add that to the E85 virtual airmass and E85 map torque tables? Then work those tables form there???

1-31-20 BBA_G5MAF_v15 1 5500 pounds.hpt

[Jonblarc7]

So I tried to just adjust the stock E85 airmass and E85 map in the the area I thought it was having the problem 700 900 1200 rpms

I looked like in my logs the zero peddle torque was 15 to 25 lower than the engine torque at will say 1 degree of timing and .25 airmass.


So I bumped it by 20 then interpolated up and down in those three columns in both E85 airmass and E85 map .



I'm guessing that was way to much LOL. Because it seem to smooth out the idle when coming to a stop. But accelerating it blimp the throttle real bad and make the truck surge real bad. I had to put it back to the tune I had in it above.

[Ben Charles]

You need lower VT with a cam, never have I raised it and helped

This is at idle regions... VT mods much like SD in regards to camshafts

[Jonblarc7]

Thanks when I was changing the tune. I was wondering if I was getting dyslexia and going the wrong way.

I'll give that a try.

[cmitchell17]

So I don't think a lot of people agree with this but when you swap out a higher revving cam and better flowing heads the torque model and MAF (unless you add a intake that changes the maf tube dimensions) calibration should not have to be touched. The driver demanded torque and VVE most certainly should be changed. I know there are more ways to accomplish the same thing and we have major limitations (don't have access to entire factory calibration or PID's ect.) than say the factory calibrators, but this seems the most logical way to go about things.

There are exceptions so you should change the torque model if you say increase compression, but for a cam or another bolt on that increases airflow the system should see the increase in airflow and reference a higher cell reference and a higher torque.

[Jonblarc7]

Well I drop it -15 in those area?s and then another -5 and that seemed to get rid of 98% percent of the slight jerking while coming to a stop. I might get a hint of it still but 99% of the people wouldn?t notice it.

I don?t disagree with you but I don?t know enough about this stuff to know.

I plan on having headers and intake added along with a wideband I have sitting in the closet. I plan to re-work the airflow after I get these installed in about another month. But for now this will work

Thanks for the help

[cmitchell17]

I'm not sure how it is on the trucks, but I've found in my Camaro that disabling the TCC lock up at zero throttle coastdown really helps with the clunking and clanging that makes your car or truck feel and sound like a POS. It helps most with the 4-3 (depending on if you have a 8L90 or 6L80), the gears above that you can leave the TCC lock enabled so DFCO can still function at higher speeds.

I have noticed with the cam now, and that I am getting a lot more clunking and clanging in the driveline during coastdown. Now I know I said that I don't believe (in theory at least) that torque tables need to be adjusted with airflow increasing mods, so I am not sure what is throwing it off or if I actually need to adjust the torque model that I am against doing.

It could be also just the increased overlap and combustion instability at low idle RPMs and the controller is trying to hard to keep idle speed and using timing to do it and causing rapid torque fluctuations. I know idle tuning is extremely difficult and there is a lot that goes into getting stability and a constant speed and minimizing NVH. I'm pretty sure the OEMs have the exact same difficulties and they also have to maintain emissions compatibility.

[Jonblarc7]

Are you talking Torque Conterter>Apply/Releae>Normal>Release.

I have it on both Apply and Release disabled in 1,2,3 and the last 3 cells in 4th.

I need to log and watch when it releases in 4th because I am getting a clunk sometimes when slowing down to make a 90 degree turn.

[cmitchell17]

The excessive driveline backlash they like to build in dosent help things. Also with 2 piece driveshafts that are supposed to cancel out vibrations and dampen noise with all these rubber bushings, I don't think helps either since it seems to add more slop and backlash.

And I was talking about only disabling lockup in the zero throttle cells, but if you want to completely disable it that's ok, but I like mine enabled so it dosent waste anything burning through the torque converter.

[Jonblarc7]

On my truck it always felt like it was try to make up it's mind on what it wanted to do. With the TCC locking in 1,2 and 3. If you mashed the gas in 1st or 2nd it would go "Crap should I lock the converter or not, shit I don't know. Let just go into 3rd and bog, OK perfect" LOL

Now at-least it gives me a consistent pull.