I think the fuel in the carbs. is held down by gravity while the car is going up and once it starts to slow down going up the fuel will be released from the graivity and rise up in the fuel bowls and possibly slosh out thru the vents I used three peices of rubber hose and routed it to the rear of the air cleaner base, on my tunnel rams I'm going to use two vacume tees per carb and hook them onto the vents with a short piece of hose and connect the vents in line and leave the ends open on both ends. I should make one up and take a picture and post that instead of trynig to describe it in words