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Message: <blockquote data-quote="UselessPickles" data-source="post: 532598" data-attributes="member: 3256">Disclaimer: Everything below is my current understanding of how things work. I'm not an expert. Hopefully we have an expert that can tell us how close I am to being right (or completely wrong).As far as I know, the varying CO settings are for equalizing the 4 cylinders to make up for manufacturing tolerances in the injectors. If the design of the air box creates an imbalance between the throttle bodies, then syncing the throttle bodies would restore balance by restricting airflow to cylinders that get more air due to the airbox design. Some people on the forum have reported that airbox modifications do upset the throttle body synchronization, but re-syncing them after the mod would restore balance.The goal of these adjustments (CO settings and synchronization) is to get the same amounts of air and fuel in all cylinders regardless of inherent imbalances due to design and manufacturing tolerances. It would not make sense that the engine would be tuned to use different amounts of air in fuel in different cylinders, because that would reduce smoothness in both physical vibration and power delivery.As for why you would want individual fuel mappings per cylinder, I think that is to make up for slight differences in compression and cylinder size due to manufacturing tolerances, differences in the scavenging effect of the exhaust on each cylinder, etc., but I haven't really looked into it so I could be completely wrong.</blockquote>

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