I have a 3310-11 and mine looks just like the big ball. I run the silver spring and went up to a 37 sqirter and it ran just as good as the car did with a 650 mighty demon, it idels better but after reading this I might try it with out the ball

I'm 98% sure the check ball in mine is the larger one. I had the carb on the Challenger apart last weekend to change the spring. BTW, this carb is new (2 years old).