Same for all N/A cars. Good thing is. The K20A will respond to light tuning such as I/H/E and Hondata. Which would not cost the world if you do it smartly!
IMO, if you want to do it cheap, Custom SRI/CAI - Under $300 easy, Headers on EP3 are pretty good - leave them if you want or take them out and cleanout the ports. Get a custom 2.5 mild steel cat back - Between $300 and $400 pending on what muffler you use.
Then Hondata which would give you the most gain once you done it. Can be done for under $2K and the car would be doing 13's (Highish).