Auto Shift Time & Firmness

[Billiumss]

When you have a stock auto tranny and stock converter, what would be the safest you can reduce the shift times? 20% or could you shorten it up more?

Also with shift firmness, how much to adjust for this?

Is it more a personal preference?

Bill

[jimmyblue]

You can zero the times, and the PCM will just "give it
all it's got" for shift pressure. For some reason I've
seen people recommend upping the shift pressure as
well (like maybe the adaptation process has less than
full authority, or maybe you just don't want to wait for
it to learn?).

Both of these only affect the PWM line, not the max
hard line pressure. Presuming that the trans is safe
at max hard-regulated line pressure (which it sees at
WOT anyway) I see no particular internal downside to
upping these params.

When you command -25% times with the Predator it
zeroes the adaptation time table.

[Dom]

I just took out the min pressure you see in the first column and replaced it with one over. This way at least the trans doesn't see min pressure. In the future I might start increasing when I learn more about it.

[MNR-0]

Dont be afraid of shift pressure. Its fairly safe to play with it in tuning scenarios. You wont damage anything if you command max. line pressure and decide you hate it. You can always scale it back.

Ive played a lot with mine right from max. line pressure to 75% and now at around 50% from 280ftlb on. The track will tell me the remainder of the story, as you dont need to do a neck jolting shift to maintain acceleration.