LQ9 engine, LS3 heads adn ls3 intake with stock ls3 injectors. I have a holley fuel rail running a return fuel setup. A AEM regulator 30 to 150 psi. The supply runs straight to the fuel rail goes through teh cross over then fills the other side, from there it runs to teh regulator then to the top of the tank. I am not running vacccum yet on the regulator. with the key forward the psi is 58 once it starts at idle it drops to 52ish. This was all fine and dandy until i tried to pull truck out of garage and it tried to die each time i braked then finally died before i got out of garage and now wont start. Ideas? Do i need to keep higher pressure at idle?

 

i have a new cam as well.

 

Depends how your injector flow rate table is set up in the tune. If the reg is referenced it will be same value, if its not referenced the numbers should increase with vacuum.

 

thanks, yea i have a buddy working his magic with HP tuners as i finish it. Just wanted to make sure on the setup.

 

I don't understand why the pressure would change when you start the engine if the regulator is not vacuum referenced.