Originally Posted by wstar

Random notes from testing: the Throttle Position (as in butterfly) data in OBD-II may be faked, but it does track something roughly equivalent in VVEL if so. I did some logging on the curves while trying to roll through the throttle smoothly and consistently using different test maps. One was my standard smooth map to 3800, and the others were modified to smoothly reach 3200 and 4200. The funny thing is that in spite of the large change in the wide-open numbers, it was hard to detect any real difference in the graphs or the driving feel.

The 4200 map did tend to ramp out a bit quicker at the end (which just makes fine-grained control with the pedal more difficult), and the 3200 map did seem a little smoother at the top, but the differences were pretty trivial. It seems like the numeric maximums are largely irrelevant within reason. What causes throttle behavior changes is the shape of the curves (since they all started at the same low-end values, the 4200 map had a sharper slope than the 3200 map).

Also, based on testing, and based on reading some google search results of UpRev guys posting on other forums, reaching WOT at any RPM was never an issue on this car. Even on my stock throttle map, I can get the TPS output to peg when I stab the throttle from a stop in first gear. Apparently running a map like mine does remove some throttle latency in lower speeds/gears though.

What's left to test really is playing with the curvature. Right now I'm running linear (by percentage) from 18.8% to 96.9% on the table, and the TPS outputs still look fairly non-linear when rolling through the pedal smoothly. By that I mean, it goes relatively smooth for a while, but in the upper region it tends to just skyrocket relative to pedal position (i.e. more in the shape of an asymptotic graph), which I guess means I need to run the numbers up a little quicker near the bottom and flatten out the deltas in the upper-mid part. Going to try some other curves on the data and see what makes it smoother.