pressure
I seem to get in unique situations. Everyone seems to run a 1 qt overflow tank. On my past 2 cars, it would always over flow if I added enough water to when it cooled down it would not suck air back in. On the roadster we kept adding capasity till it worked right, on the dragster had to add a 2nd tank hooked in series. It now holds enough water that only water is sucked back in. Works great like this, and I now suck off the bottom. I could just never get it to work with 1 qt. Good Luck.PS I run my over flow tube from the can out back past the chute just in case it over flows, it will not get under the tires. :wink: