Vacuum Lines

     My vacuum lines are 3mm inside diameter and have about a 3/16" sidewall so they don't collapse under heat and vacuum.  They also provide a better "signal" to the map sensor when under boost, there is less fluctuation.  My original parts store lines collapsed at vacuum when my engine got hot, this was not good... 

     The vacuum line source comes from stock nipple on the intake manifold.  It then T's to various locations.  It first goes straight through to the fuel pressure regulator.  The T's go to the boost controller, the blow-off valve, and the MAP sensor for Megasquirt. 

The boost controller is basically a housing with a spring, two ball bearings, and a screw.  When you twist the screw, it puts more pressure on the incoming air pressure from the vacuum line.  This "fakes out" the wastegate into thinking I am using less boost, which in fact, I am using more boost.  This lets me boost anywhere from 7psi to 21psi.  You can buy all the parts at home depot for under $5.

     I also replaced the stock brake booster vacuum lines with higher quality silicone ones.