Holley Model 2280 Carburetor

Fig. 9, Power Valve Adjustment:

1983 MODELS
1. Remove carburetor from engine, then the throttle body from carburetor.
2. Clamp throttle body in vise with mixture screws facing up. Ensures that vise jaws do not damage gasket surfaces.
3. On all models, drill a 5/64 inch pilot hole on manifold side of casting around each mixture screw, Fig. 10, at a 45° angle toward concealment plug, then enlarge hole to 1/8 inch.
4. Drive out concealment plugs with a blunt punch.
5. Reassemble and install carburetor, using new gaskets.