I run the Nitto DR's and I generally run between 22-25 psi. Seems to hook up pretty good for me at those pressures. I've never tried any lower than 22 psi though.
Edit: I try to launch around 2700-3000 rpm. Anything less and it bogs.
I angle my side mirrors down a little and spin them until I start to see smoke. 6-8 seconds probably. When I roll forward I can hear the rubber sticking to the track!
With the KB, you may want to leave the line off idle the first time and then try to go a little higher each time until it won't hook anymore.