How To Tune Carbs Idle Transfer Slots
Big cams with low idle manifold vacuum require a larger opening to flowsufficient air to make the engine idle. If the throttle blades exposetoo much of the idle transfer slot (arrow) at curb idle, then the usualfix is to drill two small holes (starting at around 3/32 inch) in theprimary throttle blades on the idle-port side of the blades. This showsthe proper amount of idle transfer slot exposed.