Auto Trans Tuning - Kick Down Conditions

[tim510]

Guys,

Fiddling with my Dad's FJ20ET datto ute. It has a VL 4N71B Jatco which I'm setting up as standalone (no TCU).


At the moment I have a switch on the accel pedal that activates the kickdown, but it only does it at 100% throttle. It seems a big clunky. Great if you are drag racing, not so good if you are losing speed up a long slow hill. You can boot it, make it shift down and then feather the throttle. I'm looking at a better solution.


I have a spare ECU output and would like some advice regarding kick down conditions.

I have inputs for Road speed, RPM, TPS, engine load (all the typical EFI shit). These inputs can be used to build a rule controlling the output.


I'm thinking :

IF TPS > 70% - kickdown

or


IF RPM <3500 and MAP > 5psi? - kickdown?


Am I on the right track?

[BigJonWB]

I guess because turbo some sort of vacuum modulation is out.

[tim510]

I guess because turbo some sort of vacuum modulation is out.

It has a vacuum modulator and shifts up well with this, but doesn't seem to work that well on the turbo car shifting down. Its a NA box on a turbo engine. I have a 'turbo' modulator to be installed. Replacing it on the car is a bit of a pain though.