[What'saCobra?]

Carb problems can be fixed easily, cheaply and correctly, but you can only pick two from this list of three variables.

The most effective fix for road racing is deep-six the dual set-up (sell it and the manifold to a collector/poseur or a psudo-drag racer) and go with a modern Holley HP series 850 or perhaps a 950 if you really have a hot cam, flowed heads and big pipes. Other carbs will do, but Holley's racer carbs come perfect out of the box. Call Holley, tell 'em exactly what you've got and purchase accordingly. Listen to their view on current manifold choices, unless you have a serious and well-justified preference.

If NASCAR thought two 4bbl carbs was effective, they would all have them after petitioning the France family for a rule change.

Like all carbs, final jetting (leaning her out) is up to your choice of exhaust color, chrome pipe blueing, the importance of another 1/2 a tenth of a second less ET and piston-melt risk. Otherwise, don't screw too much with it. ***** to Holley if it isn't absolutely perfect and follow their instructions to the letter...

Short of that suggestion, there are several culprits that may be solving your problem. It isn't clear to me if you have center-pivot carbs currently. These later designs provide for correct fuel bowl levels, when set up correctly, despite any two-axis accellerations (left/right or fore/aft). Without these it is a lot of luck and fetteling to get them close and they may never be quite satisfactory because of inherent design flaws that cause them to be accelleration sensitive.

So, what to do cheap.

First, get the specs and mechanically set the fuel levels in the bowls. The usually means bending the float tang until the tang or the float is a specified distance from the bottom of the bowl. (While you are at it, make sure there is no fuel INSIDE the brass float, which will cause the level to be excessive high even if the tang bend is correct.) Grab a pair of the clear bowl plugs to visually ID that the actual levels are below the lower lip of the plug threads. Adjust & test.

If no joy, clean the bowl inlet valve seats and if the shut-off valve pins are steel, consider installing Viton-tipped pins. These work great and will tolerate higher than normal fuel pressures and still seal. While you are here, clean out the valve seat orifice. Test.

If no joy, certainly try lowering the bowl fuel levels a bit by closing up the tang adjustment dimension, both in case they are too high and you might cheat a solution thereby. Test.

If no joy, install a fuel pressure gauge and check fuel inlet pressure. It should not be much above 6 psi or so, including when you rev the engine (if you have an additional mechanical pump). Install a Holley pressure regulator if much above 6 psi. Measure, adjust and test.

Bruce from Winter Park is correct, there are fuel vent extentions you can install that will reduce the splashing of fuel overboard into the venturi(s) during various accellerations. Buy the Holley Catalogue, read, learn and get the bits. Install and test.

If no joy, check the linkage and ensure there is a little initial play or clearance upon throttle application. If it is zero lash, engine movement from shifting, braking and variable torque will cause the accellerator pump(s) to dribble or even squirt unintentionaly. While you are here, make sure the pump levers have an initial loose fit on the pump lever cam. Vibrations can cause the pump(s) to dribble. Also, linkage can twist with accelleration and engine movement and open the throttle a little, enough to cause the pumps to dribble. Set them up loose and see if it helps. Measure, adjust and test.

Anyway, while this is far from complete, you get the idea. There are other little things you might screw with, like raising the idle rpm a bit to help the engine clear when you stomp on it just before the apex, but they are either too diddley or trying to fix something that ain't designed right in the first place.

Oh yea, and dump those little Stellings air filter CHOKES if you have them. They are trash and eat fuel and hp.

These suggestions are offered along with good luck wishes and are not intended to be a complete treatise or sequentially perfect.