I would not mess with the carb yet. First of all, you noticed the idle dropping? Meaning what exactly? You mean it consistently idles lower than before? or goes up and down? or you don't like the low idle? Second, there is an idle adjustment screw to open or close throttle blades. That's how you set idle together with trans either in neutral (manual trans) or in D (Auto). The carb you have is a Carter Aluminum Four Barrel (AFB) with an Edelbrock name. It is a good carb and very easy to rebuild. Your friend is wrong about the need to file anything. If he says it "sticks" behind the cam, doesn't that make it idle too high? but you say it's "dropping". Adjust the Idle to the specified RPM's (600-700) and be done. Idles can go down over time because of dirty air filter. Don't understand "not having much luck" adjusting idle, it's just like pushing on the pedal. The idle HAS TO GO UP! I don't know the age and condition of ignition or carburetor components but I would: Refresh distributor components, new plugs, wires, air filter, time it, then set idle. In other words, a tune up. Fix exhaust leak. Super bitchin motor. wave

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