FWIW, my 92 eagle talon (turbo, awd) had a stock boost of 10.5 lbs. Tuners regularly increased the boost "safely" to ~16 lbs. The hard core drag racers were increasing boost to 20-25lbs. (with stock pistons) Bear in mind though that the Talon/Eclipse were generally regarded as being unusually accepting of boost increases. i.e. the pistons were overbuilt.

A very big concern is to make sure that you have sufficient fuel delivery. (if not detonation can result, and that is BAD) For starters, make sure that the fuel pump and injectors are up to the new duty. On the Talon, it was generally accepted that upgrading the fuel pump was good enough up to about 16-17 lbs. Beyond that, injectors needed upgrade.

As a point of interest,for the Talon, I read a general calculation that each 1 lb increase in boost, you get about 7 more hp. I imagine that the t5 turbo would likely be 7-8 hp per lb increase. Seems like this was consistent with IPD's estimation of hp increase with their ecu reprogramming.