how to make a switch for street/race boost or high/low

[compression]

This how to article is going to tell you how to turn your stock bcs and your mbc into switchable boost controllers.

Items needed: stock bcs, about 10 feet of wire (if that), mbc, a toggle switch, 2 vaccum tee's and about 5 inches of vaccum line and 2 female connectors for the bcs wiring, and a few zip strips.

First you want to take your lines for your mbc and tee it off between your pressure source and the mbc, run a line from the open end of the tee to the stock bcs (prefferably the flared end), then put a tee in between your mbc and your wastegate and run a line from the tee to the other end of the bcs. like this



now take your 12v switch wire, and run it through the firewall hook a female connector up to it and connect it to one of the male spades on the bcs (i found it doesnt matter which it is) now connect your wire to the switch inside the car, and run a 12v wire from the switch to the fuse box.

now simply take another strip of wire (enough to run to a ground) and put a female connector on one end and connect it to the bcs , then find a nice ground and attach the remaining end of the wire to it.


now find a nice home for your switch , i just put mine near the cd player.



now you have a switch that lets you toggle between stock boost and user specified boost. its kind of fun to feel the difference in between boost levels by flipping the switch from stock to high boost while boosting.

make sure to keep your wires away from anything that may harm them.




edit: there was a little confusion about the wiring, i suggest the 2 female connectors because some people cut the stock bcs connector off of the wiring harness and leave the wires exposed , if water grounds those wires out it usually leads to ecu failure.

and here are 2 rough schematics