Ultra XP850 Almost there!

Bewy said
Somehow, I do not think all these people can be wrong....[ below ]. The last link is from the late John Passini, who wrote several books on carburation. He was English, hence some of the quaint phrases....
Something else to think about:
- opening the throttle to activate the main system also pumps fuel in from the acc pump; how do you determine what is pump shot...& what is from the booster?
- if the O2 sensor says 'rich' about the same time the main system is expected to start, how do you determine whether it is JUST the main system fuel...or fuel coming from the tail end of the idle system?
- the reaction time of the O2 sensor to mixture variations.

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Read that VERY close.

They are talking about bleeding off signal. That only happens at high air flows when the booster has started.

C.F. Taylor covers this in his books. Larew and Obert do as well.

It seems these authors only discuss what the MAB does once the booster has started. Not what happens before it starts or getting it started.

Like I said above, at best they are half right. They really need to clean up how they write it because it causes massive confusion.

EDIT: read the last article very close. He is saying what I’m saying without actually saying it.

The emulsion stack gets its air from the MAB. Read it very close.