Ok 499+ see dyno
Mods were ported Eaton (oe supercharger), pulley for about 16psi, K&N intake kit, larger maf, no cats mid-pipe, cat-back exhaust, and dyno tuned.
shane, maybe you're at altitude? I'm at 600' asl. My car ran 12.40's/117 with 420rwhp on stock tires. I had nothing removed except most of the gas, 1/8 of a tank or so. I used ET Streets at the track with all the mods. Around here, 600rwhp (that's over 700 at the motor) in a Mustang will put it deep in the 10's at over 130mph with traction and decent driver. 9's with weight reduction, drag suspension and no mercy
BlackMica, if you don't already have one, you might look at a diff brace from Billetflow or something similar. The best piece of advice I can give is if you start to wheelhop get the f off the throttle. The IRS can be a weak link and it hates wheelhop