Bksnake

Ok, some of you may remember back in August I had a baseline Dyno pull done in a bone stock configuration. I was hot that day and I ran the hell out of the car on the way to DynoSpeed. Bottom line is the RWHP was 393. They said the car was "heat soaked" and if I let it cool down it would probably be around 420 HP.
Once that was done I ordered the power upgrade from Ford. CAI, Axle back exhaust, ProCal tune. I had planed to get a excalibur X3 and a custom tune from DynoSpeed. It made such a difference in the car I had decided not to get the custom tune. Why? It was a great improvement over bone stock! Well a month or so goes by and I think I need a little more power, not much just want to break the tires lose in second.
I change the pulley to a 2.6 on the supercharger, new spark plugs (1 degree colder) and custom tune. This is November, much cooler now and the car stayed overnight. The Dyno numbers are now; 557 RWHP (That's a 164 hp gain for less than $3,000 worth of bolt ons)
Since then I have had to put Steeda Billet lower control arms on to help with the Wheel Hop.
The car is Awsome!!! Now I have to find tires that will hookup! Any suggestions? G force? Nitto? I would like to keep the stock size. 285/40ZR - 18. I don't dirve the car in the rain so I would consider Street Drag Slicks. Car is a 2009 Shelby GT 500.