hi fella,
your currently in stage 1 tune (running 14.7 psi = 1 bar boost) which should see you to around 270bhp. As above post you can run up to 330bhp on std comp (although i'm not sure how long it'll last, depends on how many miles the motor has done and how well its been looked after) !!! anyway you don't want to start just turning up the boost and hoping for the best, as you'll need a specially mapped chip anyway !!! as the stage 1 chip will be set up for a max of 1 bar boost and the standard 2 bar map sensor is on its limit !!!!!!!!
cossie tuning stages have been tried and tested over the years so your best off with going for the green injector, 3 bar map, t34 turbo route IMO !!!!
stay cool
paul