spitting through carbs
First the particulars. 1600 Duetto. 10458 cam on intake, 10320 1750 SPICA cam on exhaust. Timed at 104/104. Cam marks are on the outside edges of the cap marks towards the fenders. 40dcoe 27 carbs with stock jetting. carbs balanced, and idle screws out 1 full turn. idles well with zero turns on the idle screw. 123 non programmable ignition, set on the 1600 advance curve, and timed at a few degrees above the static timing mark @ 1200 RPM idle. Cap, rotor, coil all fairly new. I've been trying to tune out a stumble when put under moderate load after poking along at 2500 to 3000 RPM. I can get it better, but I can't tune it all the way out. There's also a sporadic spit through the carbs between 2500 and 3000 RPM, under load or at idle. It runs good otherwise. Starts well even when cold unchoked just fiddling with the gas pedal for a minute or two. Any suggestions, or have I forgotten how 50 year old carbureted cars used to run?