Originally Posted by Joseph Davis

Is your STD syphillis, and has it started to rot out your brain yet? Spin the Grainger valves, duh. :1

Originally Posted by Speed Phreak

Hi all, not many people know me because I'm rarely here. However I was compelled to post up my homebrew staged boost controller. Let face it, we're all here becuase the most of us are cheap/broke speed junkies. I'm always on the look out for a good deal or creatively cheap way of doing things.

My car has traction problems (like most FWD chassis turbo cars do)... 6~7psi most of the time will burn down 1st and 2nd gears without careful roll on throttle application, any higher boost than that makes my first 2 gears useless period. This is on a decent suspension, a Quaife LSD, and BFG DR's. I've always wanted some way to control boost over speed/gear, but short of buying a AVC-R or doing some in depth electronics work that prolly won't happen.

I figured why not make myself some sort user of selectable MBC(s)? So with a trip to the spare parts bucket I cobbled together a little 3 stage selectable boost controller that runs W/G spring in the first stage and MBC settings on stages 2 and 3. Total cost on the whole rig was about $40....cheap enough I suppose. The majority of that cost for me stemed from the "Grainger" valves that I purchased to use as ball/spring MBC's($9/per). Also I purchased a shift **** with 4 buttons intergrated into it from the local Autozone for $15 on sale...I've seen them for this much online as well. Your own MBC's can be whatever you having laying around/purchased but they have to be ball/spring type. ** Vacuum bleed type will not work with the diagrams I have provided. I can however produce a diagram that will work, but it will be much more complex than the current design.**

The basic principle I designed this setup around was to allow me to run multiple stages of boost without having to fumble for switches or take my hands far from the steering wheel/shifter.

The "Grainger" valves used in my setup fit perfectly on the honda/acura purge control solenoid. They can be purchased at your local Grainger store if you can find someone with a commercial account, they don't sell to the public(part # 5z763). If you are unable to do this McMaster carries the same pressure relief valve, part # 48935K25. They sell online to anyone. Both will need a { 1/4" female pipe --> 1/8" barbed hose } fitting.

The fitting and "Grainger valve" looks like this -->


The real deal for your visual learners


Here is a diagram for ease of assembly.




The shift **** I spoke of earlier...really made things come together well. It is basically a 4 button wireless transmitter with a brain box the has the 4 outputs. It's a cheap peice but works none the less. You may need to do some relay/electrical tomfoolery depending on your own designs. I'm happy to provide diagrams of my own setup or help if there is interest.



Everyone enjoy...