Has anyone figured out what tables need to be modified to prevent the dreaded talked about ZL1 and SS 1LE bog at launch? I have 2018 SS 1LE with bolt ons.
Feels like car doesn't come alive until 350on. When I would think it should just light up the tires.
What should I be looking at or modify to make sure I don't have this issue?
Thank you
It would help you to post the tune file, logs of it running and a detailed list of the mods done.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
throttle opening.PNG
So from this screengrab you can see when I stab the accelerator, the throttle only opens enough to match the Barometric pressure which was 98. As engine speed increases it keeps opening the throttle more to maintain the Kpa to atmosphere. At 2000 rpm it opens fully and stays open.
Is this normal operation that it only opens as much as it needs too? My driver demand is below 100% at launch but goes above 100% as speed increases. I upped that some and it didn't help as far as I can tell but I'm bumping it up again and checking.
What else should I be looking at?
Thanks for your help in advance!!
Post the actual tune and log if you want more than speculation.
I realize there really isn't any gains if the throttle opens more at this point since it's already at atmospheric pressure, but more checking if this is normal operation.
ok, I will get one loaded here in a few
You should be able to make the throttle match pedal if traction control is off
I'm not spinning at all when this happens, it's hooking. I've also tried it with Traction control off and same thing happens.Originally Posted by sevinn
I would be curious to see some of the other settings the tune throttle wise. There are a few settings on the DD tab that could do a little bit to alleviate this, and some work with virtual torque.
In Airflow-electronic throttle, everything was maxed out from factory. Except pressure ratio during a fault, which I don't think that is my issue. I have adjusted the virtual torque, lowered the top end to allow the car to deliver the requested timing. I could try increasing peak torque values below 2000 rpm and see what that does. But not sure if it's really needed or not since the Map sensor is reading atmospheric pressure.
There's alot more to it than that. You aren't logging max torque so we have no idea if your peak is above max which should be above delivered. There are some tables on the DD tab that can affect opening rate. Lots of other little tweaks.
Ok, I have added the max torque, and this gives me an idea of what I should be looking at. I will re-try logging the new parameters, to see if I am maxing a parameter out somewhere.
Thank you!!
You need to be logging Driver pedal axle tq, Immediate axle tq command, actual axle tq. My guess is your vtt is off and its not allowing for full throttle when launching. We can confirm this if you log these pids.
Ryan
log launch bog2.hpl
So looking at the log it looks like I am exceeding the Maximum Torque PID. But I am not sure what tables affects this PID? I raised my Peak Torque values and this did nothing. I have been increasing my Driver Demand in the low speed areas at 100% throttle and this seems to help some but now I'm requesting some ridiculous torque number. I looked at my VTT and in the Map KPA table it looks like the value should be higher than the 395 ft lb torque number but I'm not sure what else it could be?
Thoughts?
I had this same problem with my 2017 Silverado 6.2l in 4 auto and launching it out of the hole. I had to lower the vvt to get it to stop from closing the throttle at launch. In fact it still closes it a bit but way way less since i lowered the vvt. In fact when I up the vvt in the area it closed the throttle even more.
Good Luck.
Ryan
I think I might have figured it out. I found another post saying the table was in Newton meters and yep I was looking at it wrong. So when I changed it to ft lbs my table is low, so I will up the VTT in the area and see if that has an affect.
Your max tq is lower than actual tq in the trouble area so the throttle is closing cause its trying to reduce the tq to around the max tq area. You will have to tune the VTT in this area to bring up max tq and allow the throttle to stay open. Good luck
Ryan
Thanks! That is what I am trying, just gotta go make some runs.
So I have been trying everything to get my throttle to behave and no luck. When I increase either airmass or map to bring up the Max torque pid it works but it also increases the immediate and predicted same amount so net affect is the same... is there something I'm missing? I only do this in the variable cam table 0 since that is what it's using from 1k to 2k. Help or advice would be appreciated. Thank you
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