I'm trapped at the in-laws for the holiday's,
so I had some fun with the "paint" program...
This set up has little to no MBC spike, holds very strong to redline & works very well; however, in factory boost mode the MBC seems to be either leaking or the setup needs to be reworked... I am usually maxxed st 0.075 mpa. No biggy though... one flick of the switch & BAM!!! 0.1025 mpa in 4th gear.
**this setup is NOT recomended if you have a factory uppipe w/catalytic converter**

 

boy that pic looks like poo... darn it...

 

Here are some of the part numbers for a dual boost controller

Ingersoll-Rand / ARO #P251SS-012-D <---Mfg. part number

Grainger's part number #6JJ52 price $20.27
http://www.grainger.com/Grainger/wwg/homepage.jsp
(sorry they don't sell to consumers)

Some of the Factory parts if ever needed...
-Tiny brass "orfice" in the hose #22326KA120
-Lower "grey" hose #09535A100
-black 1/8" restrictor #22314KA040 <--- this is the one people loose with the 3/16"mod
-steel spring hose clamps #805908070 for one clamp.

 

that seems like a good, cheap setup.
why the warning about stock uppipe?

 

If people get too happy with a MBC the first cat has been reported to melt or breakup into the turbo & destroy it...

 

I would recommend a catless up pipe regardless of how crazy you wanna get, because as GLwagon stated, if the precat breaks up and the turbo sucks it in, your gonna be pretty pissed.

Pete

 

I didn't know you had boost Pete.

 

I'm sure this isn't new, but I finally got sick of my existing setup on my dual boost control maxxing at .075mpa so I re-drew this & will be testing it soon...
I'm fearing that I may get some increased spiking in MBC mode, but I'll have to see...

 

Here is a pic. I found a while ago...
I cant take credit it's not mine, but this did destroy the turbo from the story I heard...

 

here it is...

 

This second setup works well, the factory boost controller can waver some times, but is minimal.

 

Update !!!
In the second picture, I rotated the "Factory T" so it is a strait shot between the "Grainger solenoid" & "in line brass restrictor"...

The leg of the "T" should go towards the "Factory boost controller"

Note: try to keep extra hoses as short as posible with out kinking.
It is working better than ever...