Bac and thermowax question again...i searched
 

so i removed the thermowax and fast idle cam from my tb
my question is can i still keep the bac if i removed all of that stuff already?
my question being because i broke one of the studs for my bac and it has 3 threads left. id like to keep it but i think it would simplify things if i just removed it, anyone have any insight, the reason i removed the fast idle is because my neighbors are nazi and when my car idles high on startup they come out looking all angry so i dont like warming my car in front of the house.

the BAC does not need the fast idle cam and thermowax.

but to be honest your neighbors can bug off because mazda designed the car with the thermowax and pretty much every modern car has some form of cold start fast idle.

now if you car has some rediculous 4 inch exhaust with no resonators then I can see their problem. But I leave my house at 4am in my t2 w/ racing beat and nobody complains one bit.

Officially, that must be the strangest reason ever to remove the thermowax and cold start cam. The cold idle is just 1500 RPM. Shouldn't be much louder then idle.

But what he said. The BAC is independent of the cold start mechanical stuff and vice versa. I suggest fixing the broken stud because the BAC can introduce a vacuum leak like anything else.

In additin to what's been said, the 3000RPM startup is not only because of the fast idle cam or BAC, it's also because of the Air bypass valve. That valve is mounted on the same side of the dynamic chamber as the BAC valve, just a bit to the rear. Start your car in gear (clutch pressed obviously), and it won't hold the 3000RPM.

the 3000rpm cold start is from the air bypass valve, yes, and this should be removed as it is only for cat lightoff. the thermowax fast idle is 1500 rpm.

It's both the BAC and ASV. The BAC opens a little, the ASV opens wide open.

i already removed the fast idle cam and thermowax, should i just throw them back on ? like i dont know, im in the process of swapping in a rebuild and i dont know how the idle will affect it, i just want to simplify my system and avoid putting the bac back on because one of the posts broke, but not all the way i can still thread a nut for blockoff plates. but not enough to put the bac on,

Its all up to you. Either you leave everything off and you have to hold your foot on the throttle pedal until the car is warmed up, or you put the BAC back on without everything else: the thermowax, fast idle cam, and asv. Set the idle at 750 rpms and bam, thats what it idles at the whole time without any high idle.