What is the leanest and richest AFR that is typically considered "safe"? I have done some searching on the web and I've seen people talk about the ideal AFR settings with a tune, and people warning of leaning out a car. But at what point is the AFR considered too lean that it hurts the engine? Anything above 13 under full load or 14.7 at idle or is there another general AFR point that I am missing? From what I have seen, ideal power is 12.5 (rich) to 13.5 (lean) but under normal cruising and idle, you want to be around 14.7. Would idle or cruising at 15, 16, or 17 be alright? Or is where the AFR falls under load what is important?
airfuel.jpg
__________________
12' Nissan 370Z - Build Thread:
Link
15' Nissan GTR Previous Toys: 15' Nissan 370Z, 12' Nissan 370Z, 00' Chevrolet Corvette, 00' Toyota MRS 2ZZ & 6MT Swap