It has been 8 months since I changed from the original tune on it so I can not remember. I had not towed anything with the van before i did the gear change, tire change and new tune. I did log some data the other day so I could try and see what was going on in the background. It seemed like there was a lot of spark retard throughout the driving session. I was curious being a torque based system am I seeing knock retard or torque management retard? Is the optimum tune one where there is no spark retard due to knock or are the modern efi systems fast enough that they can manage the knocks with adjustment? The spark retard was all at partial throttle, a wide open throttle run showed no retard from what I could see.
Thanks
Scott