Problem with most of the “better” factory Toyota autos is, they have electronically controlled valves, you can almost do nothing to them in the way of shit kits ect to get them changing quick
I went through this drama with my car. My only option was to ditch the auto part of the ecu, thus creating a manualized auto, so I could then play with the guts.
How ever, didn’t choose this as streetabilty is rubbish, and my car is big and slow.