1 pointwww.willtheyfit.com bang in the sizes there and see what you get or what you are hoping to achieve. wheel size will be on the wheel somewhere probably. If they are 14 then your tyres will need to have lower profile to give similar rolling diameter for gearing and clearance issues. So 185 55 14 is a common size tyre for lupo, but others will also work depending on how low the car is, wheel offset, etc..
1 pointDidnt know VW did one: https://en.wikipedia.org/wiki/List_of_discontinued_Volkswagen_Group_petrol_engines#1.0_R4_16v_Turbo_82kW
1 pointCan we have some pics. It would be nice to see it.