fattest cam in a 340?

Sure sounds like the balancer may have slipped. Word to the wise. Throw that dial back timing light in the ditch. They are worthless. Too many variables. What if the knob is not on quite right? Them little degree stickers ain't hardly ever in the same position. Just too much room for error. Unless it's a computerized, digital light, chunk it. A good old standard non dial back light is your friend here. But at least that dial back light did possibly show you that the balancer is slipped, so it did serve that purpose. I would just not try to set timing with it. JMO