Don't go too high on the stall speed, since it will increase, to a higher RPM, once your engine produces more torque, near the stall speed.

The torque limits of the transmission are set by the weakest link, which may not be the torque converter. On a specific transismission model/make, there may be specific weak links, but the wider bands and more clutches in the clutch pack are common improvements to increase torque, without slipping.

The valve body is often modified to increase the shift pressure on the clutches and bands. It is usually setup to increase the speed of the shift. This ususally just consists and drilling a few holes larger and changing a couple of springs and/or pistons, which changes the rate of the servo filling.

The higher stall torque converter will reduce turbo lag and soften the firmer shifts of the valve body.

Keep us posted. I have done this on some American cars and may do this on my S4 TIP, in the future, since Porsche, BMW & Mercedes are too flashy and the RS6 is a little large and pricey.

Don