Ok, I'll check launch with max redsol = 3. Which launch RPM are you use?
It's rolling anti-lag, not off-line launch.
I do not use fixed rpm. It keeps (saves in variable) whatever rpm currently the car is when i activate function (pressing pedal to the floor and pressing CC button).
At around 3500rpm it builds 1,0 bar easily. At higher rpm even more.
Of course maybe you're running something like a GT40, then that's a bit tough to spool on a small engine and requires a transbrake...
I implemented my rolling anti-lag on the car with GT35 and it does like 2,0 bar (relative not absolute!) easily

On GTX30 gen II it does 1,6bar but on mild ignition (around -15 as i remember).