Are the stock injectors and T-Body enough to run with the 227 Cam in a 95 Z with shorty headers,2500 stall and 3:42 in the rear,or do I need to go bigger ?
This is a street car only.

 

The stock injectors will support 355 flywheel HP at 85% duty cylce or less.... push them closer to 100% DC and they will exceed 400 flywheel HP. Doesn't sound like you are quite at the limit, if the only mods are the cam and shorty headers. 48mm TB probably isn't at the limit either.

 

What about if you add stock heads with just a 3 angle valve job?

 

That isnt adding much,if anything...so stock injectors are fine.