How to Tune With Air Bleeds

Air bleeds control the amount of air distributed to the venturi and emulsion lines.

Tuning your carburetor enhances the performance of your engine. An improperly tuned carburetor can result in excess fuel usage. Air bleeds administer a controlled amount of air to the venturi to push the fuel out of the fuel jets. An approximate ratio of 13 lbs of air to 1lb of fuel will give most engines the most power. Do not attempt to adjust your air bleeds without previous experience or the guidance of a mechanic.

Things You'll Need

• Flat head screwdriver

Instructions

1. Locate the air bleed screws on your carburetor near the accelerator pump nozzles and boosters. The inner screws are the idle or low speed air bleed screws which work with the idle feed restrictions to control the amount of air delivered to the fuel lines. The outer screws are the high speed air bleed screws which control the air in the emulsion tubes and the timing of the main circuit.

2. Tighten the screws with a flat head screwdriver for a smaller air bleed. Tightening the screws for a smaller bleed on the inner screws sometimes fixes transitioning problems by restricting the amount of air delivered. A smaller bleed on the outer screws increases the high RPM mixture by bleeding less vacuum strength.

3. Loosen the screws for a larger air bleed. A larger bleed will thin out the air mixture by bleeding off more vacuum strength in the low air bleed screws. On the high speed air bleed screws, loosening the screws makes the air-fuel mixture richer and affect the linear fuel curve.

References

• MoparMuscle; Carb Tuning Magic; 2005
• Camaros: Forum -- Adjusting High Speed Air Bleeds

Resources

• RhinoRacing; Carburetor Tuning; Paul Yaw