Process to log and tune ford procharger for mid throttle load non-linear acceleration
I would like some help: What are the right PIDS to diagnose having the pedal feel go super numb after getting ETC, DD & torque tables settled for the rest of the tune. I haven't messed with distance tables, could it be that? As the car goes onto boost at 2500rpm rolling from .4 load to full load it takes smashing the throttle to the floor to get meaningful acceleration in 2nd and 3rd.
This is more of a general question of how to tune than specific details; I don't want to spend a bunch of time going through every single thing about my car again and everything that's been tried to have start over again later. I also don't have time to dig through the entire history of hp tuners to figure out something I will do one time for this car. My main frustration has been that really having someone dyno tune it for me would be best but I've been ghosted 3x on getting a dyno session so I'm back to working on it myself on these more advanced tuning processes.
You can accomplish this by tuning your driver demand table.
Search for my thread on setting up a math parameter to track pedal count, then graph it alongside absolute load and scale them until they track together at minimum and maximum. A good pedal feel for me, is when these two trend together well. While logging roll into the throttle as linearly as possible, and at different speeds. Then review the logs.
If absolute load has a spike compared to pedal, you need to find the section of driver demand and reduce torque there. If there is a dip, you need to increase the torque demanded.
You don't need to go crazy. Most of my changes are 30 lb-ft or less, and this made a big improvement. My bottom row has increases of up to 70 lb-ft though. A pedal count of 542 is roughly 90% throttle, so that row should be requesting about 90% of the torque in your torque tables at each load/rpm combination. Take note that this doesn't mean to look at the bottom row of your OP torque table for those values. You need to look at a WOT run, see what your load is at each RPM, then figure out what torque that represents in your OP torque table using interpolation.
Here's a tune file and log that works pretty good except for the throttle roll. It was discovered early on the 3.7l really hates having the DD table messed with. None of the files I've reviewed have touched it and my experiences were it made response unpredictable instead of smoother so it went back to stock. In the screen grab from starting at minute 5:38 you can see etc error go nuts which drives fuel trims into tizzy then once the car comes back through that load range it does it again on the other side. That's discernible in the seat as similar to a misfire but the plugs are good.
Just because people gave up trying to tune DD, doesn't mean it cannot be done. Most people don't touch the Coyote DD table, including Roush, but I had great success.
Here's the layout that was running while I logged. It's got a lot of histographs but I'm only focusing on the torque based ones at the moment. the time mark is 16:49:56 through 16:50:05 or 5:38 through 5:45 depending on how the timeline is set up in scanner. *edit* replaced scan layout so that the bottom histograms are just of the pids logged. Also added a screen grab from about the 9 minute mark which shows the throttle angle waffle despite being commanded to open smoothly by the throttle position. It happens again at 27:23 and at 27:30.
Is this dip in throttle angle responding to an error in the torque tables or to some other area that still needs tweaked? looks to be about 70% load each time.
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