I would personally stay away from the brakes all together, but thats just me. I would go with a vacuum manifold, but get it from say... connection that goes to the crank vent or something like that. I am not sure what is most convenient for the GT, but I just don't like the idea of taking vacuum from brakes that work off of vacuum.
Stay off the booster. Get a vacuum manifold and tap off the intake manifold or the fpr line. Hook everything but the wastegate up off the manifold. The wastegate should be tapped on a nipple off of the turbo compressor housing to ensure that you get proper boost levels.
Everything that needs a vacuum source is hooked up to the FPR line in mine car...including the wastegate. Titan Motorsports did my IC setup and didn't notice that my turbo does not have nipple on it. The tech hooked everything up to the FPR line and said that I won't have any problems with it; so far he was right :bigthumb:
I have the electronic boost controller, AEM, and the guage that determines when to open the wastegate is connected at the manifold. But the boost solenoid that is what opens the wastegate, and keeps it closed when needed is hooked up directly to the "nipple" at the turbo outlet, just like XplayaX said.
Ah yes, didnt read it right. When I had my MBC hooked into by brake booster line, it came disconnected one day. I didnt notice any adverse effects in braking. Just because you have a vacuum leak doesnt mean you lose all vacuum in the system, because the motor is still sucking in air. It would have to be a huge vacuum leak to zero out the vacuum in the system, if thats even possible.
so what u guys are saying is get a line to to the wastegate from the vacuum manifod and tee off that one to the manuel boost controler and then from the mbc go to the turbo compressor housing cold side nipple.
You need to know how a wastegate works in order to be able to understand how the boost controller works. I am assuming that you have an external wastegate.
A wastegate is basically an exhaust valve, and at the top of this exhaust valve is a diaphragm. There are two connections on the wastegate, one on top of the diaphragm, and the other underneath it. You controll boost via manipulating the amount of pressure that is allowed to be exherted on either side of this diaphragm. There is also a spring inside, and the manifold pressure must greater than the spring rate, thats why you have different spring rates available for the same wastegate.
Now that you understand that (hopefully) you should undertand how a boost controller works. It keeps the manifold pressure pushing on the top of the diaphragm, until the desired psi is reached, then allows that pressure to be exherted underneath the diaphragm, effectively opening the wastegate and reducing the amount of exhaust turns the turbine in the turbo, controlling boost.
NOW, if you have an internal wastegate, all you have to understand is that the MBC will keep the boost off the wastegate actuator, until it hits the desired setting, and then will allow it to flow, activating the wastegate.
ok i see how it works you get a line from the vacuum manifold or the turbo compresor housing nipple cold side to the in nipple of the mbc and from the out nipple of the mbc you take a line to the wastegate.right