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View Full Version : Newbie Help Tuning T43 6L90E Advice



V8NHH
June 16th, 2015, 12:57 AM
Have issue with my auto (LSA powered GTS), had some mods done to engine - higher boost (9.55 crank pulley - otr -1"/78 headers hi flow Cats, 60lb injectors)
Concern I have is with my new mods, I find that when cruising on motorway in 6th gear around 1500rpm and want to accelerate with minimal throttle it feels like the car is bogging down or lugging (similar to when you are driving a manual and are going like 30 MPH and are in 6th gear and try to accelerate).
Im getting into boost (kpa increases) once at around 2000rpm she clears and pulls good
Car was tuned but trans tune not touched. (identical from what can see to CTS-v stock tune)
Im at 528rwhp 918nm torque

ECM torque model has been adjusted by tuner

Help / suggestions please

I have only just got EFI live V2 so trying to learn logging etc.

joecar
June 17th, 2015, 10:11 PM
Post TCC apply/release curves (paste into xls file and post it).

V8NHH
June 17th, 2015, 11:18 PM
Hi Ya
Have copied TCC tables into xls and attached.
Bit more info running on motorway I notice when gas it in 6th gear (part throttle) from 1200rpm up it seems to pull but not clean (until around 2000rpm), I have seen the revs drop aswell and you can actually hear the supercharger whine when normally driving you don't notice it ?more boost?
18528

FYI my PE is set at - B0157 is set 95kpa
B0156 is set 8%

joecar
June 18th, 2015, 02:36 AM
I think your TCC is staying locked when RPM goes down low.... we might have to raise the TCC release curves.

V8NHH
June 18th, 2015, 09:06 AM
Would that be just in gear affected eg 6th?
How much would I need to adjust by.
I can mod and then log (just need to confirm what PID's needed, either ECM-E67 or TCM-t43)

joecar
June 18th, 2015, 12:21 PM
Yes, start with the affected gear... just raise the release curve a bit (but make sure it stays under the apply curve), and go for a test drive... repeat until satisfied.

You could then try to see if the problem happens in the next gear down, and repeat.

V8NHH
June 18th, 2015, 05:29 PM
Well that worked!!! nice one

What is the crack with the activation/release? I see in lower gears it doesn't activate and when you are in hot mode its very tight gap between apply/release.
I think it will take more driving yet to nail it on the flat shes good, just have incline to sort now - speed drops from 70mph to 50mph and goes up hill so when accelerate partially lugs a little.
If I understand it a bit more reckon could adjust out, or see about 6>5 gear adjustment.

Side note: DFCO being enabled or disabled no main reason for it? just put back to original to see if difference (my economy changed from 24mpg>18.8 since mods/tune, driving style same!)
Tad scary first time loaded change!!!
Thanks for help

joecar
June 19th, 2015, 10:54 AM
Yes, play with it some more.

Do not assume that the OEM got the tables right (they have various ulterior motives, some of them conflicting, some of them overriding all others, e.g. fuel economy and emissions reduction override everything).

InTruckDesign
July 13th, 2015, 09:12 AM
Sorry for digging this back up, but your condition is exactly what my 2011 Suburban 2500 is doing. It is a boosted(TVS1900) 6.0(L96) with 6L90 and I get what you describe, most noticeable when just rolling into the throttle and not commanding a downshift. I am building boost also when it happens so after paying more attention to the issue it really feels like the trans is holding it back.
I am fairly new to the 6L90 tuning, if you don't mind could you explain more of what you raised/changed and by how much? Like did you change all the tables?(normal,pattern A,pattern B,Hot) I would greatly appreciate it, truck runs great and pulls hard from a dig, just feels flat when rolling into the throttle.

V8NHH
July 13th, 2015, 10:56 AM
Yep in end I played with and am still tweeking my 6th gear tables, as standard my car is going into 6th very early so you get the bogging feeling. I have been adjusting the Speeds that 5-6 and 6-5 gear changes happen at(as in kph) and also having a play with the apply/release of torque converter.
I haven't perfected it yet, I'm making small changes testing going back adjusting.
As Joecar said just don't make release above apply.
I still need to improve mine but because better I don't notice it as much.

InTruckDesign
July 14th, 2015, 12:04 AM
Thanks. Looks like I need to plan some time to play around with the apply/release.

InTruckDesign
July 14th, 2015, 09:20 AM
I was able to make some changes to the apply/release tables and noticed a huge difference. Basically raised each by 10%. I am going to tweak them a little more to get it even better.
I know to make sure not to exceed the apply speed with the release speed, but is there a minimum gap I should maintain? for instance say if my apply for 3rd gear is 35 and my release is 31, can I bring that gap closer? TIA.

joecar
July 15th, 2015, 05:14 PM
You need some hysteresis to avoid oscillating between release and apply.