I couldn't see clearly and probably missed the post, but are you using the EVC 6? If I was to run high boost, I would love to take advantage of the target PSI per gear. Of course, it'll need to be optimized for the tires being used. Since I run street tires, I'd probably set mine to 6 PSI in 1st and go up from there.
At < 6.5 PSI, I can get it to fishtail in 2nd around 4k RPM from a roll on a good day. After things heat up a bit, I hardly break traction afterwards. I've not tried launching the car yet haha.
BTW... I finally watched the video with the speakers on