1.5 degree of timing and 100Hp???

[RSlo]

I know an extra 100Hp is pretty silly but I was wondering if someone can tell me why such a difference. 2016 M6 P1X. I have been using engine brake torque and a math for horsepower. I'm fine with the engine brake torque calculation maybe not being overly accurate but I would hope it would show directional differences. Two runs one at 14 and other at 16ish up top. Only other obvious difference I see are the cams are in different locations. 14 degree one stayed in optimum power for the most part. What I am unsure about is about a 1/3 of the way through the second run it jumped out of vct optimum power and was in best fuel economy. Only difference between the two tunes was adding a little more timing. I've attached the logs and current tune file. Any thoughts or insights to help a noob out would be appreciated

[murfie]

Pay attention to your MBT value. When you go from 10* detonation limited, to 15* detonation limited, yes the ECU will think you are making 100hp less.

[RSlo]

Pay attention to your MBT value. When you go from 10* detonation limited, to 15* detonation limited, yes the ECU will think you are making 100hp less.

thanks Murfie. Was looking over logs and tune. The scans are showing my MBT around 29* or so I can't to find where you are referencing the 10* vs. 15* even looking through the tune. Also still confused why it was in VCT best fuel economy mode vs. OP. Trying to learn through the forum and appreciative of the knowledge. Actually enrolled in the tuning school ford class in a couple weeks to hopefully help my understanding of this platform overall.

[murfie]

The difference from MBT to spark advance between the logs you posted. Its a 70 ftlb difference, when converted to HP that could easily be over 100 hp in higher RPMs. MBT is the known reference point in which the ECU determines where the estimated torque is going to be, the further you are from it the less estimated torque is going to be. 5* further away from it is a lot just like adding/ subtracting 5* from the true spark would equal a lot on the dyno.

MBT difference.PNG

[RSlo]

Ah the difference between BL and MBT. Thanks! So what is the best indicator of tune changes? You mentioned the ECM thought the car was making XYZ torque vs the other. In reality was the power still close? Indicated by MAF and load? Thanks again for your input.