Too many Rabbits...
ceffie, with stock exhaust and 0.9 bar boost = 14.2 if you are lucky.
mid 14's would be more correct.
especially after say first 2 runs.
that stock cooler would be nice and toasty, exhaust temps will be huge, the poor stock turbo would be about to give up.
Stock speedo and stop watches... let me guess, you are measuring 400m using your dash trip meter as well?
cause that will be absolutely accurate on a 20 year old car, not to mention one that has 245's making it even more accurate.