i think under 11.s is hard to get, even with experianced drivers( not me) and even driving the same car for years, you cant estimate what your car should run at the creek, just take it down and have some fun, dont expect to much the first few time till you get used to launching as i have seen a lot of people get dissapointed after running bad times the first few times.
Usually it will take you serveral times to get used to the car and if you have a standard clutch youll be racing twice befor you have to go home with no clutch at all.
spend the money get some good tyres, and now that its winter boost it up a little and go have some fun down the track. also remember gtr's take off the best bouncing off the limiter.