Pinking....AGAIN.

[gaz666]

Timing is good, plugs and gaps ok, good fuel pressure, clean air filter, new fuel filter, vac advance working etc. My 350i idles and runs good,pulls well, but when engine gets around 90 degrees it starts to pink around 250-300 rpm when i burry my foot in the axminster! To me this seems like i need to duct some cold air into the air filter. Any ideas, or am i barking up the wrong tree?

[gaz666]

Engine has done 70 thousand, took out a plug and looked at piston crown with mag light and fibre optic at TDC. Looks very black. This must be running to rich, so if i reset mixture and check CO hopefully pinking will go. Ive used a colourtune on other engines before and had good results, anyone tried it on a V8? Any tips, etc.

[gaz666]

Can you confirm if clockwise at the mixture screw on the flapper is to richen and to aim for around 1.5%-2% on c/o, and plug gaps .08mm. Thanks.