Closed loop question
 

I'm still new to turbo's so bare with. But i am a studying engineer so i will get it.

-If this is closed loop it reverts the excess psi back into the intake and away from the closed throttle. to prevent it from going back to the turbo.
-But if the excess air is placed right back into the system (im guessing before the turbo), how can it make you run rich? YOUR THROTTLE IS CLOSED?!?
-the turbine will not be spooling hard so that recycled air will just chill in the system.
*Does it mean that the density is whats important. I mean really the air just might run out of the intake filter the wrong way if the turbo isnt spooling.

DON'T YELL AT ME... JUST THINK ABOUT IT?! and then answer nicely

RE: Closed loop question
 

the main function of a bov or a dv is to relive air pressure, so the throttle can close quicker, and the air trapped in the tubes wont wash back into the turbo trying to spin it in the opposite direction, on a closed loop system the boost air from the dv, there is a sensor that samples the air that the dv displaces then reports it to the maf in conjunction with the maf reading, would cause the ecu to either add or take away fuel to keep the a/f ratio to the factory setting, if not metered correctly the computer thinks that there is no boost to be metered and fuels up the engine to attempt to create boost

this is my understanding of it

RE: Closed loop question
 

Maf before the turbo, usually run DV's
MAF after the turbo, they run BOV.

It comes down to this. The metered air goes past the MAF, this is what determines fuel.
It's either used or recirclated back into the itnake, since the air is already metered, there is
the correct ammount of fuel added. Really it has nothing to do with throttle, except for the action
of the DV. So if the air goes threw a BOV, the ECU still things it has all that air in the system, and
makes the car run rich.

The other way, the air is not metered untill it is pressurized. So the car has no idea how much
air there is, so ther is not fuel added. Since the fuel is not metered yet, it uses a BOV. Only adds
fuel when the pressurized air goes past the MAF.