Don't know about removing the springs but it sounds to me like as the blower heats up you losing pressure so the signal to the carbs is changing. I would play with the springs in the metering rods when the engine is hot, this is something you can do on the side of the road. I would go for a heavier spring. Edelbrock recommends the orange at 5".
Quote:
Two model #1405 carburetors should be used on engines with positive displacement superchargers, such as GMC 6-71 blowers or equivalent. The following calibration changes make an
excellent starting point: Primary Jets - .101" (#1429); Secondary Jets - .101" (#1429); Metering Rods - .070" x .042" (#1450); Step-up Piston Springs - 5" (orange, stock); Needle & Seat
assemblies - .110" (#1466). This calibration has been tested on engines ranging in size from 350 c.i.d. Chevys to 440 c.i.d. Chryslers with good results.
