personally mate i think n/a engines (cars that are naturally aspirated i.e. no turbos or superchargers) are very hard to tune!
I have driven a saxo vts for a year before my golf and i was stuck on what to do.
Here a couple of tips for more power!This is what i did to my saxo (yes i know what a dirty, chavvy, horrible car lol)
1. Full exhaust system(decat)
2. Performance cams £300 and remap, another £300
3. Throttle bodies,jenvey (£3500) off these expect massive bhp gains!pricey, yet very very very very worth it, and sound crazily good!
4. Supercharger
5 Turbo (£5,000) for an average priced full turbo kit.
6 Sell it and buy the 1.8t
Hope this helps