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[croc7]

Hif44 with BDK needle on a1360 w/an Isky ‘torquer’ camshaft & LCB. I’ve been told anywhere from 14.5:1 to that ‘A series engines like 12.5:1 to 13 air/fuel ratio at idle.’ Any recommendations or opinions would be welcome. Thanks

[unburntfuelinthemorning]

Without using a gas analyser it's often recommended to adjust the mixture to achieve the highest idle speed and then weaken the mixture to just before the point where idle speed drops again. 

 

Gunsons colortune is a good way of setting idle mixture too.

 

The factory settings range from 1.5 to 4.5% CO which is in the region of 13 to 14:1.  David Vizard in the carburettor section of his book seems to like it weaker at 1% or 14.5:1.

 

Somewhere within these ranges should be fine, it's not too critical unless you need a particular CO and HC reading for a sniff test.  If not just aim for the smoothest idle.