Dual quads versus big hammer!!!...

I'm too lazy to read the whole post, but did you ever try removing the springs?
I think some Thermo-quad drag racers did something similar.
I'll go back and read the rest:)
Thermoquads have 1 spring on the "T" plunger that holds the metering rods. But yes, basically the same function. The plunger was pulled down by vacuum at start up. The difference is, the TQ "plunger" could be adjusted in height (raising or lowering the metering rods) with a Allen wrench. That was a nice feature.