I been researching the web for hours now and I can't find the information I need. I have a 2015 Sierra 1500 5.3 and I would like to know what size injector come stock as well as the LPH on the stock fuel pump. I'm looking to turbo this truck but I want to do a very mild set up if I can keep all the stock component and push 5-7psi boost in will be more than happy.

 

You have a direct injected motor, not a port fuel injection motor. Those injectors run at crazy high pressure up in the 3-5,000 psi range and I don't know the lb/hr but it's alot. If the truck is factory flex fuel they should be okay for around 400-500whp from what I gather.