[Snake2998]

Sorry for late reply - couldn't get logged in until now.

My comment is that all following this advice must be losing huge power due to overly rich fueling and most probably retarded timing because of a problem most probably confined to cars running in very specific conditions, not normally experienced on the road or during track days i.e. with a dual plane manifold (or side-draughts) and very high cornering G's.

In normal conditions you would not be coming hard onto the throttle until the cornering G's are significantly lowered (and hence fuel starvation reduced) ) unless you are in "drifting" mode so your AF ratio should depend largely on your specific driving situation. It is normal that AF ratios below 12.5 : 1 are confined to turbocharged cars with high compression ratios combined with retarded ignition to reduce detonation but this does cost significant power.

If I were in the situation where this could be a problem I would certainly fit broadband AFR sensors in each bank to see if there is a genuine problem in my situation and use profile rather than accept the cost of fuel and power loss due to some "generic' opinions based on experience in unusual (for me) driving situations and natural and reasonable reputational preservation by engine builders.