For $1500, your best bet is to do an intake, exhaust (yes you will pass emissions) upgrade the ecu (chip) and replace the plug wires with some larger ones. That will make your car sound better, and run a bit faster. (Probably around 240-250hp vs. 225). Those are just basic BPU mods though. The most expensive of those is the exhaust, unless you go custom, which is usually cheaper (and sometimes better!) If you really want to dig into it, you could also port match the heads, or run larger injectors with a fuel controller and a 50-100 shot of Nitrous. (That puts you into VR-4 power ranges. All the above with a 100 shot would put you at about 365bhp. But you'd also need to replace the stock clutch, it craps out pretty quickly)