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Rice Over Wheat


I asked almost the same question a couple months ago.  Larger injectors spray more volume of fuel when opened for the same amount of time.  So your AFC is hiding 31% of airflow that the ecu reads in order to trick the ecu into holding the injectors open the same amount of time it would have if the 450s were still in.

So a lot of these guys here with 650s start rich at say -20% or -25% on 650s, and tune towards -31%, getting leaner as long as they can control knock/timing based on their boost level.  But different factors can play in so each car is different for its ideal setting. That's why you want to start richer and work leaner.  But without a logger or Link you can't do that safely, which is why others recommend you to keep it at a safe level like -25% HI.

Oh and it's never safe with a woman driving, but that's another matter entirely. :sneaky:

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ORIGINAL: jlh077464

Also one thing is, with the neo you have more rpm points that i didnt put up...it starts at 600 then up to 1k 1.5k 2k 2.5k..etc etc...up to 8k if i recall correctly....so you think @ start up...low throttle i should start out with (-20) across the board, and work from there. At least thats what im getting.