Direct port siphoning

[5mall5nail5]

Hi all,

Recently put in 0.5mm jets in 6 intake runners behind the throttle body. Works great but I can tell that my overrun isn't as clean as it was for a split second or so after I close the throttle. I can deal with it, but I know the vacuum is sucking some fluid from the lines. I came back after a pull and saw the lines were not full. Are there any small check valves that Aquamist recommends and is it even worth while? Just another thing to fail. I can deal with it, just looking to see what other people are doing.

Thanks,
Jon