I really don't know what the numbers mean, so I couldn't tell you for sure about the significance of negative values. I think just flipping the sign on them is probably a bad idea, as that would be a big jump in value. I know it's nothing as simple as "values below zero cut fuel/spark and go into engine braking", because we can easily get engine braking at deeper pedal positions than the chart goes negative for at high RPMs, e.g. if you play around with the pedal while sitting at say 5-6K rpm in 2nd or 3rd.
Keep in mind that in my original experiments, I didn't have to move all that far away from factory values to get very ugly behaviors that weren't drivable *at all*. Experiments are at your own risk, and scary things can happen. Some of the odd behaviors I remember from testing maps that were just a little too much out of range or out of shape in various areas include things like:
1) The accel pedal seeming to act normal for the first 15-20% of pedal range, and then you move it a hair further and the car suddenly leaps into full throttle out of nowhere, scaring the **** out of you and breaking traction.
2) The pedal seeming to act normal to nearly full throttle, but then when you hit full throttle the car acts like it's past a rev limiter (when it isn't) and cuts fuel/spark dramatically, shocking the drivetrain if you were in the midst of acceleration or shifting.
3) The pedal seems extremely unresponsive for the first half or so, so you keep pushing your foot down, then it suddenly responds out of nowhere and floors the engine..
etc...
Be sure you're on a wide open road clear of traffic if you experiment with crazy values in this table...
Last edited by wstar; 09-30-2013 at 11:22 PM.
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