It will need a fine tune. It does learn on its own. You gotta set parameters on when it starts to learn. I’m having a hard time fine tuning cold starts. But other than that truck runs great. Holley sets these ECU’s to run a little in the rich side. Dialing it in professionally or taking the time to do it is a necessity. I fouled a set of plugs in the process of learning. Holleyforums has great input on installation and tuning.