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I haven't gotten e-mail notifications this thread had been updated, glad I checked.. Lots of new info and more questions.
So first, the car is stock other than the dinan tune.
I'm still experiencing little (worse?) performance improvement. I do see psi hit 13.5psi (it would hit high 11's pre tune on my ultragauge) but only for a fraction of a second before it drops, so the tune is in (I don't think a tune can be "part way" installed can it?)
At the track, the 335's I'll run with, I've maybe regained maybe 20' of about 150' loss during a 1500' straight. To me the tune still is showing almost no change.
I've also been recording sensors with torque and racechrono apps with obd. I'm not sure what I should be looking for yet but one thing that I find odd is the throttle position sensor drops from being in the 90%'s under WOT to 50%-70% for a half second or so, roughly half a second after going full throttle, before it jumps back up to 90%'s. I've checked the 02 sensor thinking maybe it's causing throttle to be cut but it's stable before, during, and after it happens. So is calculated load, but absolute load drops hard during this stutter (or is it reverse of those two sensors).
The throttle position drop is VERY reproducible. I'm talking _every_ single lap at the track you'd see a half second of 90% throttle, half second of bouncing around 50%-70%, then a 5-7 seconds of smooth 90%. Also about a quarter of the laps it would also have issues for a half second again sometime during the 5-7 seconds of straight (I go from about 60mph to 105 during the straight). O2 during these drops is stable, about middle of the voltage range. I can even reproduce off track. 1st gear I rarely see it but 2nd, 3rd, 4th all have throttle position drop after about a half second of WOT. I've still got to check if knock detection is doing something, there's probably a PID for that I believe.
I'm also currently trying to track down if it's related to a certain RPM, as I didn't have rpm monitored during my last track session. And I've seen a few graphs during street driving that I happened at the same rpm range, I just need time to verify.
I've run some 0-60 runs (apps, I know they're crap, but ballpark close) but I'm getting about 6.7s right now. I'd hit 5.4s regularly with the app before the tune, but there are a lot of variables (weather for one, gas, whatever) that change but over a second slower seems a little strange and I need to investigate further.
If anyone has recommendations on what obd PID's to monitor, I'm all ears. Only thing as I've said is I know the throttle sensor reports it's dropping.
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