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The first major change is that the pressures are now based off of a torque map for the engine. This map uses throttle position v/s RPM to model engine torque. I had always thought that the pervious software lacked an RPM component to the shift pressure tuning. Bam!, torque map in your face. Admittedly my map is essentially based off of a little info and a lot of educated guess but should be pretty close to actual engine output
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I wonder if using actual engine load would be better RE: MAF or MAP + throttle position, this would automatically compensate for altitude, increased air filter restriction , engine wear.
In the 80's / 90's GM used a throttle cable and vacuum modulator on the front drive 440T4 while it was full hydraulic shift. There should be a tech manual outlining why this was done.
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Next major change is two stage pressure control during the shift. You have modulator and accumulator pressures to control how the off going clutch releases that then switches to a second stage separately controlling those pressures during the application of the on coming clutch. This is some really hardcore shift tuning here. Admittedly the learning curve is very steep but now that I've wrapped my head around it, the new tune is coming together exceptionally well. Unfortunately there is no manual, no guide, just a few hints from Whip along the way.
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Something to consider on the two stage pressure that would not be so apparent when you were running single stage. If you double fluid pressure, the flow increases by less than double. This will give you a non linear pressure vs shift firmness graph.
Are you looking at fluid temp? Fluid is thicker when cold so valves react slower and orifices appear to be smaller as well.