Gumball
06-16-2017, 08:08 PM
If your car has a Holley carb and you are experiencing a drop in rpm when braking, especially under hard braking, when the engine isn't under load - i.e., not engine braking, just coming to a stop with your foot on the clutch or with the transmission in neutral, it's likely your rear float level. Drop it in small increments and the problem should go away.
To lower the float level, put a box end wrench on the rear adjuster nut (on the top of the carb) and use a wide flat blade screwdriver to loosen the lock screw. Then, turn the wrench a quarter turn or so clockwise. It helps if you mark the adjuster nut (not the lock screw) as a frame of reference. Tighten everything up and you're good to go. In my case, the float level was set just about right - a little dribble out of the sight plug opening on the side - but a 1/2 turn of the level was enough to make the stumble go away.
To lower the float level, put a box end wrench on the rear adjuster nut (on the top of the carb) and use a wide flat blade screwdriver to loosen the lock screw. Then, turn the wrench a quarter turn or so clockwise. It helps if you mark the adjuster nut (not the lock screw) as a frame of reference. Tighten everything up and you're good to go. In my case, the float level was set just about right - a little dribble out of the sight plug opening on the side - but a 1/2 turn of the level was enough to make the stumble go away.