[TurboGT]

So, he sent me another email last night (which i wasnt expecting on easter, kudos for that) stating hes having an issue commanding the shift but it taking too long to execute, and that another file was attached. This is the only input ive gotten during this whole tuning process, which as someone who is as involved and descriptive as I've been, giving him any information I can, im rather annoyed with the lack of info on his part. I digress.

No file was attached to the email. So there goes another day wasted. Wifes been driving a 12mpg truck 50 miles round trip to work, which is getting rather expensive. Fellow ST guys, Do remote tunes usualy draw out this long???

Anyway, I figured it wouldn't hurt to change the trans fluid since its been 38k since the last change. Fluid came out nice and red and had no smells or debris, so thats reassuring.

So i go in and comb over the logs. It appears 1-2 shift command is being done at 5700, and is actually being executed At 6500. 2-3 is being commanded at 6500, so of course it is hitting almost 7000 before shifting. I also noticed at the very bottom of the PID list a little pid called "predicted engine torque source" which turns from "none" to "rpm limit" at the time this engine jerk occurs.

TL;DR So basically its just the natural length of shift timing needs to be accounted for and the engine is tagging the rev limiter. 🤦‍♂️

 

[TurboGT]

Yesterday he replied with more info, and a new file which fixed the 2-3 rev limit concern.

He also reassured me that the MAF tables are in fact skewed so lb/min of airflow isnt an accurate Gauge of power anymore. He said its not done yet but it is making well above the average of 17 lb/min ive been seeing the last few revisions, so that's no longer an accurate number. I see that timing has been practically Nothing (1 to 3 degrees of timing while under full boost, no KR) so im hoping theres a lot of room there as well. Haven't done any more power tweaks since the 2nd or 3rd revision.

With last nights revision comes todays homework. He wasnt happy with how shaky the boost control was. Had me swap to the original boost control solenoid to see if it made any difference and take another log on the same file. I also decided to bring my mityvac home and test the bypass valve, bypass solenoid and hoses, and wastegate crack pressure. All seem good there.

I asked if he wanted me to tighten wastegate preload, because, you know, learning stuff from the ST world. Will see what he comes back with tomorrow.