If your suspension is stock, I would take off your intake and header (you can keep the exhaust) and race in H-stock where you can actually be somewhat compeditive. If not, your going to have no chance. Also, invest in an autoX driving school. Some of the fast car near the detroit regions are POS festias but the drivers are bad ass. Since your in a sol and it is not a VTEC sol, your lacking so much hp and there is really no way to gain it. You can do intake manifold, racing cat or straight pipe, your intake header and exhaust, and some ignition stuff and that is about it. The si and s sol are not the best compeditive wise for DSP (the class that the sol goes to with any mods). Run in stock class, it is alot cheaper.
In stock class, this is what you want to do.
Exhaust
Some dot rated slicks on oem size wheels (check the rules to see how wide you can go)
Down grade or remove front sway bar (to get more over steer)
Good shock absorbors (springs must stay stock)
Upgrade your OEM drop in filter (spoon makes a good one) but must mantian the stock style (flat)
With this set up, you in your sol can be pretty quick