Blockage in Holley Baseplate Passage
On the primary side, the idle ports are offset. On most Holleys, the idle fuel is taken from the down channel by a horizontal passage with mixture screw forming the control valve.
Looking from the bowl toward the body....
Outer holes go the the idle ports (primary side)
a cut away from @yellow rose
and the full casting with fuel level in wells with engine off.
Open up the secondary throttle a little more and you'll see these tiny ports are in line with the transfer slots.
On the primary side, the idle ports are offset. On most Holleys, the idle fuel is taken from the down channel by a horizontal passage with mixture screw forming the control valve.
Looking from the bowl toward the body....
Outer holes go the the idle ports (primary side)
a cut away from @yellow rose
and the full casting with fuel level in wells with engine off.
