Jpar, what do the nozzles look like? I've had situations where I've had as big as .060 squirters on heavy foot brake cars with converters that were too tight.
If you have some small drills and a pin vise, I'd start in the high .04xx size and drill it out until the bog goes away.
It may also be its coming on the booster too late, and without digging into what you have I have zero decent guesses on how to fix that, unless it has a main air bleed you can make smaller by a few thou and get it on the booster a bit quicker.