How many lb are the stock injectors on the tc? Also what is a top boost level for tuning a TC without upgrades?

 

The injectors are huge, no need to worry about them at all. The fuel pump(s) would be the first thing that need upgrading assuming you're running them dry, but thats probably past 500hp.
The map sensors read upto 22.5psi and the turbo can reach that in the midrange, at the top end it falls to around 18-20psi so thats its limit. But i would suggest some intake/exhaust/ic upgrades to free up the flow.