we had a qjet on the 69 gto and it used to be like.turning on a garden hose of gas when you opened the throttle

 

We used to call them the quadrabog carbs. Lol

 

I had big Carter Thermoquad on a '69 Dart 340Mopar, would bog down, sound like a foghorn, caught fire twice, and as you said, Very hard on gas. I swapped it out for a sweet Holley 6210 spreadbore, Major improvement with instant response, easier on fuel. When I would give her the juice, even in 4thgear, would feel like a passing gear when the mechanical secondaries would open up.-Lord I miss that car.