[D-Bo]

well yeah you could start with a new filter but the problem with that is the piping will still restrict air flow.. so it won't help you very much at all.. get some intake piping and you'll notice a huge sound difference along with maybe 5hp (max).. after that, get headers, full 2.5" exhaust, then it gets expensive.. if you want to change internals and raise comression then you'd get quite a bit of power out of that but that'll cost you $2500US (don't know how much australian).. i don't know if they make superchips for the sr20de but you might find something like that on ebay.. if you wanna really feel this power then get new suspension (shocks & springs OR coilovers).. that could be a start