sweet #'s man! Thats gotta be one crazy ride, I'd doubt it would last long on the street w/out the traction control. I was doing a little boosting today and could totally feel the TC kickin in on my below 400rwhp Z, w/as much power as your making I'll bet your TC is workin overtime...
Are you planning on doing any drag racing this year? If so did you buy drag radials yet? I've been using this calculator [ http://www.turbofast.com.au/Drag.html ] to figure HP vs. ET. Its works pretty good, I used 3606 for weight 367.7rwhp for my car and it came up with 12.468, my best run at the track was a 12.47. I plugged in your numbers (531rwhp) and got 11.03, with the TC and drag radials I think you could hit it. With NOS your in the 10's..