i should tell you, the reason i say that is there is another member here named taemachine who can out-drive me in autoX by at least 10 sec. on stock suspension, you can check out mine in my profile, all he has is tires and thats it and no power mods. so it just goes to show that the driver is the best part you can put in a car.
If he is on race tires and you are on crappy street tires...trust me, that is more than enough. Now, don't get me wrong, I am SURE there is some skill involved. However, just to give an example... There is a guy that autocrosses here in Idaho and he is an INSANE driver. He took 2nd at US Nationals about 3-4 years ago in his SM2 RX-7 (Fastest damn thing I ever saw. I was working cones, and it was right next to me...and then it is gone!!!) Anyways, He now drives a bone stock 1.8t Golf. The only thing he has is race tires. Anyways, on the same day he decided to drive another guys heavily modded (Suspension, cams, etc...) Golf 1.8t. The only difference was that the Heavily modded golf didn't have race tires and the stock one did. Anyways, same driver and the Stock golf beat the modded golf on the same course by 6.5 seconds!!!! So, if that gives you an idea.
On a side note, I was STS this last year and I was running on Falken 451's which everyone knows are not great for autoX. It was all I could afford at the time... Anyways, I beat a few Corvettes consistantly that were running RACE tires. It just shows, that the Celica is an awesome handler and with some driving skill you can beat much higher classed cars.
Sorry for my novel.