If your AEM UEGO AFR gauge is reading lean after installing the parallel fuel rail mod and adjusting the fuel pressure regulator to 2.6bar at idle as recommended, it's likely indicating that the engine is not receiving enough fuel to compensate for the increased airflow from the boost. You should consider increasing the fuel delivery to achieve the appropriate air-to-fuel ratio for optimal combustion and engine performance, which may involve adjusting the fuel injectors or increasing fuel pressure further, ensuring you monitor and tune accordingly to avoid running excessively rich. Let me know, if that does help you. I would love to help you more. I will come back here later. Right now, I want to visit https://academized.com/buy-literature-review here because I want to buy a literature review from that website because writing an essay assignment is a very big headache for me and I can't write all of it by myself. That is why I prefer to take help from online essay writer.