Is that the PCV port that is capped? Why?
You must run the PCV to the primary side of the carb with a thick-walled,designed-for-vacuum, hose.
The way the set-up looks now, your engine will flood during cranking. Which may be great for a cold start, but terrible for hot-starting.
By running the PCV to the primary side, you can see how the vapors would get a chance to mingle with the fuel being discharged from the transfers and idle-ports. This helps smooth the idle.
If you were to run the PCV to the Secondary side, and I'm not saying that you did, then that air could still be mostly dry when it gets to the cylinders, and then the back four cylinders would run leaner at idle (I suspect all the time), and the engine would idle rougher.
If the PCV hose is NOT a thick-walled designed for vacuum, hose, it is very likely to collapse or partially collapse, messing with your AFR, under high manifold vacuum.
But you are making progress, yahoo.
