With a big cam change, and tuning for VE. I understand that tuning for drivability we can set the ECM to Open Loop, and zero out all variables until we have a commanded lambda of 1.0 and with a calibrated wideband, do a constant speed test to see where we are at with out actual readings throughout the map range on a constant speed dyno by setting a lambda error.
If we plot this data against our VE table, we can get a pretty good idea of what our CAM is doing in the engine and adjust the VE accordingly.
My question is, its all fine and dandy doing it to 2500rpm or so, but how does everyone do it for RPMs all the way up to 6000?
For example, if I'm commanding lambda of 1.0, am I not commanding 14.63 +/- AFR?
If that the case, what are the drawbacks of tuning this way. Are we not going too lean using this method?
I understand that on a boosted car, 13:1 is dangerous, and most likely 14.7 is not because its too lean to cause any damage (out of that threshold), but are the engine temps not going to go up?
My question being, we can tune to 2500-3000 maybe using lambda 1.
But for anything over that, what would someone be commanding? I'd say over 3000rpm, I start commanding 12.8 AFR or lambda .85, and plot my lambda error against 0.85?
Thanks if your still following me.
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