When it comes to tuning carburetors, the Edelbrock carb is one of the easiest to work on. The Edelbrock´s idle mixture screws are easily accessible, greatly simplifying the tuning process. The engine´s idle mixture screws control the vacuum inside the engine (manifested in the vehicle´s idle) and can be adjusted for optimal engine performance. A correctly tuned carburetor will allow your vehicle to start more easily, have a smoother idle, and as a result, provide a better ride.
Open the hood of your vehicle and locate the carb -- note the two idle mixture screws on the front of the carb. These screws control the engine´s idle. After pinpointing the idle mixture screws, turn the car on and let it run for five minutes.
Use a screwdriver to loosen the left idle mixture screw (make sure that the screw does not fall out of the carb as you do this). After loosening the left idle mixture screw, use the screwdriver to tighten the right idle mixture screw until it closes. Once you feel resistance from the screw, stop tightening it.
Open the right idle mixture screw -- apply five half-turns and then close the left idle mixture screw, just as you closed the right screw in the previous step. Once the left screw is closed, apply five half-turns to open it to the same point as the right idle mixture screw. This will ensure that both screws are in the same position.
Adjust both screws by identical half-turns until your vehicle idles at 800 rpm. Once the engine reaches this level, close the hood and leave the car running for five minutes, then turn it off.
