There is no point running 14psi (1bar) just because 14psi > 10psi and sounds better. And everybody is telling you this! and yet you still wish to run 14psi? Basically all turbos have an efficiency range, after which running more boost is mainly doing more harm then good. You may get a whole 5rwkw or so (which you won't notice when driving), but even the extra 4psi you'll notice:
* extra heat produced (more in the engine bay, never good)
* will take longer to spool up and therefore lag.. although true, bees dick in it
* very little power increase over say 10psi.
And why trash a perfectly good turbo that you may get $500 for on the 2nd hand market if still in decent condition?? Thats a $500 saving on your next turbo purchase.
If you imagine a curve, basically it begins tappering off with diminishing returns each PSI above 10psi or so. Therefore while 1bar is 40% higher than 10psi, you're definitely not going to get 40% more power..more like 5% if that.
10psi-12psi with the stock turbo is generally ample on an RB25DET, and if tuned correctly will give you 170-190rwkw with the setup you've got and its been proven over and over. Thats plenty, and with the other support systems (most importantly tyres and rear end setup), like people are saying, enough for low 13sec 1/4's if thats your thing.
Initially everybody thinks "more boost is better" but as you go on and learn a few more things, you find thats not always the case. Like many, I've experimented with higher boost, but everytime i get it tuned, the tuner goes "ba.. why bother, you're getting stuff all extra power" so back to a more reasonable 10psi (@ last dyno 183rwkw) where its been for at least 6 months now.