Technical mixture a bit weak?

[Yazza54]

Whizzed the plugs out the otherday just to have a look at the colouring. I dont know what they were like before i put the gsr on but im thinking the mixture is a bit weak now because of that extra air and no map tweak to match the extra air with more fuel. Thought this because the plugs are quite white rather than the usual nice coffee coloured. :/ am i barking up the right or wrong tree?

 

[sussexa]

not really sure but when i looked into plug reading when trying to set up carbs 15 years ago, i think they only give a true reading at the moment the ignition was switched off ie to check at full throttle you had to cut ignition when at full throttle and coast to a stop and whip out your plugs.
not sure about modern fuel injection cars but sure the lambda sensor reads your mixture better than plug reading.