If you want All Motor then you will need more displacement since you have a teggy. I would go with either a 1.8 or sleeving a 1.8 to 84mm and having an almost 2.0.
If you want Turbo power then you could keep your 1.6 that you have now and obviously boost it. You can get good times with that set up.
If your goal is low low 13's and maybe 12's then I would probably boost. It depends if you want to keep all the nice stuff on your ride or if your willing to gut some factory fixins and rough ride it.
Milan (personally, this is just my opinion, I love ALL Motor)