OSW is a pretty well prepped track IMO. I ran a 13.14 last time I was there but that next week it was cold so I went out to track locally and ran my pants off. I was consistently hitting the 13.1x. I was also using stock tire pressure.

Once you get those 60' times down you should lose about .2 - .3 sec off the ET. Some of my better runs have been when I've spun a little but that 13.07 run the tires straight hooked when I brake launched at 1500 RPM.

I also take off all my grilles when I run so that might help me out a little bit