2015 ECS supercharged C7 high and low octane spark tables look the same

I can’t imagine this is a good thing. I had someone (a forum member on here) do a tune with EFI Live that was supposed to get rid of the throttle lag sometime ago. I should’ve monitored it but I didn’t I’m a noob. About a year and 20k mi later, I installed a supercharger and had it tuned thinking the tuner (using hptuners) would sort out anything wrong with the tune. Then I started monitoring for KR on a Torque app. it was knocking pretty good under heavy acceleration below 3000 RPM. I brought it back to the tuner but of course the car decided to behave like a good boy. That tuner ended up pulling a few degrees out. But later it started showing knock again of course. So I started looking at the tune and found the high octane and low octane spark tables are the same values. When I compared to the original tune I saved of course they are different.

The guy I let tune for throttle response changed it so they are identical and the guy who turned it on the dyno for the supercharger changed the high octane table but left the low octane table matched. What I’m thinking is the old adage if you want something done right do it yourself but you have to learn how to do it right yourself in the first place so I’m in a catch 22. And I’m losing trust and the guy who did the dino tuning.

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Can someone have a look over this and see if there are any red flags that stand out? it's what i have in the car now.

I've had efi live for a long time but never learned how to tune but now it looks like i'm gonna learn, hopefully not the hard way.

The tuner, knowing you have EFILive FSV2, should have gotten you to log data pids so he can ser the conditions when knock occurs (it will never never when you're showing someone).

Did you tell the recent tuner that the tune had been touched earlier...? However, he should have been able to see that it was modified (a good tuner will first compare diff against a known stock tune for the year/model/vehicle).

I did tell him it was modified for for throttle response. Yeah I’m disappointed. So how do I start logging data PIDs? My post is a little misleading, I had a second look and I do see a small difference between the high and low octane spark tables, but in the stock tune the difference is much greater.

not really answering your point , as i'm re-learning tuning for the E92 ECM myself, but it'd be a good idea to at least throw in a stock low octane table (or get the dyno tuning guy to do so). As far as i'm aware with the E92, they are torque demand based - so don't "exact" read the timing and fuel you give it, but calculate back (somehow) the power/torque it is making and actually if you asked for more at those throttle positions vs rpm vs speed then it tries to make more - by adjusting fuel and timing. If you have no reference low octane table, its a worry you might have hamstrung the ECM from actually being able to 'better' regulate the spark ?

This is common practice while in the process of calibration. This shouldn't be detrimental although not ideal. These motors when they make power register a lot of knock and you don't want them in the low octane all the time. The knock is typically false. It is hard to tune knock on these platforms correctly. IMO the Gen IV controller did it perfect. I believe they listen far too long. I need to dig a little deeper with these but.... from what i have seen. The E38/e67 listens for about 20-25 degrees of duration. The e92 listens for 70 degrees. This strategy is being used since the E78 which was the first torque based controller. What is interesting is that gm has the sensitivity way low (10-12 standard deviations from base to detect knock) on the e78 and 3.x standard deviations from base for the E92.

Depending on your setup your knock window can be rather small between detonation and preignition and the amount of fast attack retard can surely eat up the window you have between these 2 and as such it is advisable to set High and Low the same. If you have cats this can become a real problem as you will kill the cats with too much heat and once these break and clog your exhaust it usually takes your pistons with it. So it becomes a very fine line you have to ride.