Hi, mcgiver explained how to tune a car on gas, but that must have been another type of gas set up to what I have, I can only find one screw on mine and I don't know what it is for
or called?can sombody give me the rundown on how to do it with an IMPCO (LB2)
(200m-2-2) Thank you.

Mine had a brass turn knob with Allen key in the centre it think generally you crack the nut to loosen the fiddle with the inner screw till mixtures good then tighten nut
Got a pic of the screw you found? It should be a brass fitting on a hose

I think I've got it right this time I had trouble uploading the photoes

You do not have the required permissions to view the files attached to this post.

That screw is the fuel idle mix screw should have a spring around it but evidently yours doesn't lol . Winding this screw inwards makes it richer and outwards makes leaner. Mark or measure the screw before you start! If you mess with the idle you can simply reset where it was previously ( maybe measure length of screw with tape measure?) Twist the screw inwards if you want a richer mix or outwards for a leaner mix. Once you think its close take it for a drive and see how you go, adjust where necessary

thank you I'll give it a try.