If its from IoW then its my old one, which it probably is. It was technically a stage 3+. The first in the country.
It is a GT28RS, aka disco potato. Its modded from standard marginally, i think just the intake lip and waste gate. Check the waste gate as it broke after i sold the car.
It was running 340bhp (350bhp on one RR run). That was its max and it ran this for 60,000 miles. APR will likely be reluctant to help as there were several turbos used and several mods made but they were not keen to divulge info to avoid people buying their kits second hand and copying bits etc. As its old (the 1.8T set up) they may be more helpful. Worth a post on their site on SeatCupra.net - they always responded well on that to me.
If it was mine, it served me well. dont be alarmed if it screams at you on full tilt!
I believe that even with higher octane fuel and intake mani mods similar spec turbos did not produce more power by th way and 350bhp is garretts quoted figures for the GT28RS (from memory).
If its mine, feel free to PM any questions.