[jhv48]

Ok, one more time. Adjust the idle screws to max vacuum ( mine only took 3/4 of a turn out from bottom to get max vacuum). Then, disconnect the vac gauge and put it away. Now turn the screws out another 1/4 turn. Go drive it. Stumble gone? turn the screws IN 1/8 turn and go drive it. Stumble returns, back out the screws to the 1/4 mark and leave it alone. If stumble still gone, leave it there. Sometimes the best vacuum peak is NOT the best driving setup.