Originally Posted by
paulb
The short answer is that the downshift table (Accel 2), is more exact, and the Accel 1 smooths the limits. In others words when you go into a down shift mode, the tendency is to over shoot the limit, so controlling the torque closer will help keep from "over torquing" on a down shift.
The way it does it is by using the bilateral interpolation between the cells. On the accelerator axis for accel 1 you notice that it goes from -1 to 50 to 100, and then stays at 100 for the rest of the table. The torque values change, but the accelerator axis stays at 100. The ECM uses interpolation to smooth the torque increase across the 6 100% cells, using the different torque values as kind of way points along the way. The bilateral part is that it includes the rpm change in it's interpolation calculation.
In the accel 2 table it has more exact control and less smoothing using the bilateral interpolation. The rpm changes becomes more dominate it the calculation then the accel position.
I hope this helps...
Paul
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