Do you mean the valve springs like in the heads, or do you mean like the suspension type springs, Im confused because you mentioned autocross. If you mean valve springs like in the heads, there really isnt a point to doing that unless you get a different set of cams. If you mean suspension, people seem to like the Eibach pro kit, or the H&R sports. Just look around and do a search.
I am already running steeda springs which I think are made by eibach. Not sure though.
I did mean valve springs as in the heads. The car has almost 95,000 miles and there seems to be a little ticking going on. Also, my race head friends (stock car) say that the best way to keep the engine strong and alive is to change the springs. I don't really want to do cams though.
I was thinking about doing a DIY head porting while I was at it. Just for fun you know.
Im guessing you have a pre pi headed car (96-98) If so, maybe you should consider the PI headswap. Search around for it. If you dont have the pre PI car, then Im not really sure what the tick is. I do however doubt strongly that its just the valvesprings.