Its not carb, its Single point injection, so nothing you can do there
You can fork out a fortune on exhausts, K&Ns and all sorts and never see any real diffrence.
I suppose if you K&N it, SS Zaust and header, and only run on 97, then advance the timing to suit, you will see a bit of an increase.
I think you have to accept you have a 1.4L engine and its the best it can do.
Unless you are going to pay £2000+ For full rebuilds and turbo kits, your not going to see much of a power increase. If you want to go down the custom turbo route, the car wouldn't exactly be a daily run around, and the chances are the engine would blow if you drove it hard anyway
I hope that kinda helps, I'm afraid the only way to see more power realistically is to change the engine.
If your like me you will faff about with little upgrades like performance spark plugs etc... which you May notice a tiny diffrence, but you will be used to it within 10 mins of driving and it will seem slow again.
