With a $400 budget, you have some options. Depending on how you use the car other than autocross, ie. how much snow you have to deal with, etc, there are some things you can do. I'd say get a good set of front brake pads (or even do some junkyard scrounging and get the Accord Wagon 11" front brake setup) is a wise and cost-effective upgrade for autocross and the street. An Eibach Pro-kit goes well with the AGX's, the Eibach Sportlines are nice, but they drop the car enough to require alignment kits, and that might blow your budget (don't forget, an alignment after the install!) A large rear sway bar really helps these cars, the Suspension Techniques bar is cheap enough, but I'd go for a bar that uses factory mounts rather than the S/T bar the requires drilling into your control arms. A good thing to do at the time of the rear bar is urethane front sway bar endlinks and greaseable body mounts (very nice at $25 for the set.) With all the gear shifting, urethane motor mounts and shifter bushings are a good idea. My advice? Good brake pads (I like EBC Green & Porterfield R4S pads,) a good tune-up (Bosch +4 plugs w/ Accel wires work well,) and of course, air and fuel filters. Hang on to some of your money, let the course find out where the points that need work are (and no offense, usually the driver needs the most work.)