Annular boosters on a Tunnel Ram

71GSS,
Unfortunately in your post #68, logic is missing from the first three lines.
If a larger MAB starts the mains sooner [ it doesn't ] & flows more fuel, then it follows using the same logic that increasing the MAB will increase the fuel flow even further; not stop it as you say.


Although it was not you who said it, NOWHERE in any any of the links provided in this thread does it say these simple words or words that have the same meaning: a bigger MAB starts the main system sooner. If I missed it can somebody please point it out....

Another point to remember. At some point as the throttle is opened, the idle system tails off in conjunction with the start of the main system to allow for a smooth transition between one system finishing & another starting.
I guess my comments and thoughts come from these below. It seems clear to me. From post 58

An emulsion of air and fuel has reduced density, surface tension and viscosity compared to fuel alone. This increases the flow of fuel considerably, particularly in low-pressure difference operation, at low throttle openings or lower engine speeds. Just how much of an increase (richer) is dependant upon where and how much air is introduced into the fuel flow.

Here we are discussing main jet and WOT mentioning the larger air bleed, if increased in size, will lessen flow due to pressure difference. This speaks to the MAB being larger, less flow will happen - to the point of no flow if too large. Being the MAB is above the well of fuel.

The venturi vacuum in the well is reduced (the pressure is raised) by the "air leak" from the air bleed. This reduces the pressure difference that causes the flow through the main jet. If the air bleed were big enough, the pressure in the well would be the same as in the float bowl and no fuel would flow. Think about drinking through a soda straw with a hole in it above liquid level. Bigger hole, less soda. Suck harder, not much more soda. Big enough hole, no soda. This is the means by which the emulsion system can "lean it out on the top end".

Bewy, please, I am trying to understand this. If you are reading these statements from Tuner differently, can you please quote the words specifically and explain your understanding?

@MomsDuster Sorry for hijacking your thread with all of this, but I also hope we get some info posted that does help.