I m getting a lean code from my computer what could be causing this, I just put a LT4 hot cam in it and i bumped the fuel reg to 50psi, i m using 19lb injectors
Thanks
Scott

 

There are a lot of things that can cause it. For me it was a leaking throttle body gasket. It was letting extra air in that the MAF didnt know about so the air fuel mixture was lean, my the code usually only occurred at idle speeds.
other possible causes:
Oxygen sensor
Oxygen sensor wire contacting ground
MAF sensor- sensing low air flow
Lean Injectors
Water in the Fuel
EGR not opening
Low Fuel pressure
Exhaust Leak in front of o2 sensor
AIR system pummping air into the manifolds instead of the cat
vacuum or intake leaks

The use of a scan tool to monitor the o2 sensor voltage was very helpful for me to trouble shoot it.

 

Thanks, I'll try to trouble shoot that stuff
Scott