Just got back from my 3rd autocross today. Have to say that it is quite fun and I think I'm hooked. Anyway, several people mention that the tires make a huge difference. I drive a 2001 MR2 Spyder with tires that has a treadwear of 440. These are the second set of tires and not the originals. I don't want to get a racing tire since I drive the car on the street and don't want them to wear out too fast but I do want a stickier tire that may cut some time off. Will a lower treadwear tire really make a big difference and how much? Say the course takes about 50 seconds, will it save a second, two, or three? Any suggestions on a tire or what to look for in the tire?