Throttle body vaccum port

[weagle]

What is the bottom vacuum port on the throttle body for?

Can't remember what went there and pictures I took don't show underneath intercooler piping.

[posdriftin]

mine runs to b.o.v

[Z U L8R]

i believe the bottom bung is closed when the throttle body is closed, therefore it doesn't supply vacuum, but it will provide boost. the top two do boost and vacuum , one goes to the fuel pressure regulator, and i'd recommend the only thing you ever T into that one would be your electronic boost controller if it tells you specifically to do so. other than that don't t anything off of that one. not only does it mess with your rising rate fuel pressure regulator, but i've had a plastic t crack which went to my boost controller cause my greddy profec specifically says to tap it off the fpr hose, what happened is, my boost controller wasn't getting all the boost so it was allowing the turbo to give my engine more, and my fuel pressure regulator wasn't rising to enough pressure since it wasn't getting the correct amount of boost to it, end result = detonation = melted pistons and cracked rings. the other hose off the top should go to your wastegate actuator and T into your bov. if you want you could use that other top one for just your bov and your boost guage, then use the very bottom one for your wastegate actuator since all it needs is boost and that'll eliminate 2 T's on the same vacuum/boost source. gl
Dave

[weagle]

I had the profec b and now I switched to the greddy e-01

I thought one port on the solenoid went to the actuator and the other port went to a T that went to the BOV and then onto a vaccum port on the throttle body? is that wrong?

[Z U L8R]

your last comment is confusing, but it sounds about right. the greddy boost control heads like to be on the fpr vac/boost source, so the small nipple on the top of the throttle body use for the fpr and your boost control head (the part in the car). the thicker nipple, run that across your head and over to your driver's side. this will be your vacuum/boost source for your boost controller solenoid, and your wastegate. if you want you can T off of this if you have a vac/boost guage as well. on the bottom bung you can run it to your bov. i didn't know you had a boost controller already. hope this made sense. i'm not sure about the e-01, i haven't done much boost controller shopping in a long long time, if e-01's electronic then do it like this. if it's not then leave the fpr vac/boost bung alone and run your mbc and your actuator on the bottom bung.
Dave =]