I finally got around to blocking off my EGR valve. That smoothed out the idle considerably, which allowed me to tune my 32/36 Weber correctly, which gave me a much smoother ride, better acceleration, and took my mileage from 24 to a little over 27 MPG. All for the cost of a used tin can...

Very nice.

 

-=fred=-

I ditched my EGR valve as well to find better drivability and milage!

I don't know what an EGR valve is, but it sounds like a primitive and inneficient emmisions device. Would my 83 GL have one and how would I go about removing/disabling it?

Your EGR Valve looks something like this. Your car does have one. The easy way to ditch it is to cut a piece of metal from a tin can and block the exhaust port in the valve. That way, if you have to pass a visual emissions inspection, it won't be a problem.