MNDATSUN

Great input guys. Typically I would suspect a valve, but this head just came back from a fresh rebuild by Paul Rushman, so I doubt that's it. I'm with you that it's more likely a vacuum leak, perhaps the soft mount is buggered somehow on that throat. Thanks again.

I'm running triple weber 45 152's on my vintage race car, and the center carb has begun dumping raw fuel out the air horn at all RPM's on one throat only. I've re-checked and cleaned: float level, needle and seat, idle jet, acc pump jet...so far nothing has helped. Other 2 carbs are happy. So, I'm about ready to remove the carb for a teardown and thorough cleaning, if anyone has a suggestion on what the culprit might be I'd appreciate it. These were purchased new from redline a year or so ago...have been generally reliable once I had the proper jet combo. I am running higher than "normal" fuel pressure (4.5 lbs), but it hasn't been an issue, and is something this engine likes at WOT. –Thanks