Driving me bonkers why does it keep pulling me out of OP mode?

[Bill@HPTuners]

I mean from what I can tell it should have no problem going into OP mode and staying there but its definitely hit or miss for me. Check 13m49s into the log, goes into OP mode at wot then just gradually pulls out of it for no apparent reason to start blending with a bunch of other mapped points.

This is frustrating to say the least as I lose control over the cam timing and spark timing to an extent.

[murfie]

If you notice it starts doing this right where your engine brake torque drops suddenly. This is probably causing a combustion stability limit. I believe this is because of they way you have your MBT and borderline tables setup. The ECU wants to use the knock sensorsto control knock. You shouldnt have to do this with the MBT tables. That causes a massive engine torque drop thats not true. MBT and borderline should have a smooth relationship that crosses when cylinder pressure gets high enough to cause the engine to become knock limited. This is highly dependent on the fuel you are running. Their are strategies in the ECU that allow you to set up conditions to run different octane fuels. Just make your MBT spark tables smoother so that it doesnt jump between borderline and MBT(base) values. There should only be one point where thye cross around .4-.5 load(maybe less) your MBT should start to get higher than borderline. Modifying one axis and not the other kind threw things off.

Combustion stability has a max and a min so Im not sure if the description is correct. Basically it doesnt want to see spikes, only smooth transitions, unless all torque values are spiking.

I think a way to see how many times the source PIDs were polled would be helpful. I think default its 1s. It may have missed the limit.

[Bill@HPTuners]

a. The stock strategy has different load axes for the mbt vs boarderline
b. I've tried matching them in the past and I'd run into issues if I recall correctly, I didn't take notes on what issues I had though
c. SUCH A PITA TO CHANGE THE AXIS AND REMAP THE ENTIRE MP1-15 MBT SPARK TABLES!
d. I'll give it a shot...

[murfie]

Well yeah If you make the Axis the same you need to re normalize the table values, and that could be a pita. You don't want them to be the same anyway. MBT you want more resolution in the lower loads where the engine will be able to reach that before knock and borderline you want more resolution in the upper loads where you are going to be knock limited. The main thing is you want them to cross at one point, not multiple points. Use the pressure limit table if you want to limit spark in the upper loads, or zero out the knock advance limit table in the upper loads.

Heres a 2014 OP table compared to MBT table after renormalizing the values. You can see were NA the engine becomes knock limited and borderline values are used. The borderline and MBT correction tables modify this relationship and just from understanding that you can see where the optimal conditions(lambda/temp) for timing are. There's also a "hole" in the borderline table between 1500-3000RPM and .35-.55 load where you can raise the borderline values for better part throttle engine response.

MBT compared to Borderline.PNG

And here is the MBT table compared to the borderline values. to compare why they have the resolution where they do.

Borderline values compared to MBT.PNG

With a centri supercharger this relationship wont change. you shouldn't have to worry too much about the lower loads. MBT can go almost static, just a slight drop as load increases above 1.2 load and you should just be dealing with the borderline tables in the higher load finding where the fuel you are using knocks.

[Bill@HPTuners]

You'll notice I did 0 out the knock advance limit table in the upper loads. One of the problems I found in not modifying the MBT spark tables in OP mode was they were adding timing at wot ie lets say I was commanding 12* of timing in borderline, we'll I might get a final value of 15 or 16* not because of knock advance or some other oddball adder table, it was coming from MBT spark.

[Chevy406]

I think you and I are fighting similar problems with Procharger 5.0 vehicles. I just posted a thread listing my current state of aggravation. For now I'll just sit back and see what I can learn from murfie and others...

[murfie]

You'll notice I did 0 out the knock advance limit table in the upper loads. One of the problems I found in not modifying the MBT spark tables in OP mode was they were adding timing at wot ie lets say I was commanding 12* of timing in borderline, we'll I might get a final value of 15 or 16* not because of knock advance or some other oddball adder table, it was coming from MBT spark.

That's usually an indication that your indicated/scheduled torque are high relative to your engine brake torque or engine brake torque is to low.
Usually you would fix that in the Torque model not the MBT values. This could be done by your driver demand torque or torque inverse model.

The only relationship between borderline and MBT is cylinder pressure. They don't have a direct relationship with one another where they can effect one another based on environmental conditions. Indicated torque is interchangable with cylinder pressure. Indicated torque uses the MBT value as it is advance that is suppose to create the optimal cylinder pressure if detonation was not present. Indicated torque is used as a check and balance. If engine torque is to low or high it can modify fuel, spark, or throttle to bring engine torque back into check. You may need to separate your IPC Min and Max values more to avoid the values being modified. Of course if you indicate to the ECU it's at MBT, by making it less than borderline value or borderline higher than MBT, then engine torque and indicated torque won't be too far off from each other and all this can be simplified and avoided. That will effect the ECU finding the fuels true borderline value and optimizing power output, which most don't seem to to do anyway.