Took my plugs out and found this -




Plugs 1 2 3 4 from left to right..

Now is this normal on an RS 500 inlet? I'm running 8 greens. I think the car was overfulleling, but since changing the fuel reg today and setting it to 3.5bar on idle with the vac pipe off, its lots better.

I'm just worried there is something more wrong or am i being paranoid?