from what I understand AFR can be optimized one of two ways, both require larger fuel pump and high flow fuel filter and external adjustable fuel regulator and need to be datalogged by either zeitronix or dyno.


#1. Stock injectors, mechanically increase fuel with needswings system. 1 to 1 increase fuel pressure with every additional psi past OEM 14 psi. This increases fuel volume and pressure keeps the IDC at lower cycles due to having more volume at higher pressure to handle the increased boost.


#2. 550cc injectors, tune the ECU to scale the injectors back at lower RPM (so you don't run rich at low RPM but cutting IDC and pulse width), and program for AFR through RPM range to maintain AFR.


Boostmonkey has a great write up on his fuel system with custom fuel rail and larger fuel feed lines. He installed an adjustable regulator at the end of the fuel rail and a return back into the tank. If I remember correctly he has larger injectors.