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Sounds like you have 2 separate issues. Gas "drooling" into your intake when motor is hot and sitting after parked. Second is a bog due to an incorrect air to fuel ratio during throttle tip in. I was plagued with both of these issues when my 418W was new 7 years ago. Both our motors are completely different but the carbueration problems are the same. I was able to cure my gas drooling into my intake by drilling two anti-siphon holes in the metering block of the Holley 850 thus avoiding gas dribbling out of my main jets. I never could get rid of my off idle bog no matter how I modified my Holley 850. Since I swapped my 850 Holley for a BG 650 Mighty Demon I have no longer had carb problems. I wound up trading 15 hp at the top end for 18 lbs. of torque in the mid range. Not a bad trade. Also, the vacuum reading on the dyno with the 650 BG was .5 inches until 4k rpm, 1.5 inches from 4k rpm to 6k rpm. Good luck with the 2x4 setup Jon.