Write Up: Boost Controller and External Wastegate top port w/pics
 

I bought both manual boost controllers from Donald and decided to show how to install them with an external wastegate.

https://www.homemadeturbo.com/forum/index.php?topic=72836.msg858192#msg858192

http://img343.imageshack.us/img343/1...llermc9am6.jpg

The black one is the same as a Turbonetics.
The red one the same as a Turbosmart.

Both are bleeder type valves and should not be used inline with the wastegate.
Bleeding into the atmosphere is also not recommended.
By using a closed-loop system, it will help prevent boost creep and surging with ambient temperature changes.

I found several diagrams for this system, but mspaint always wins:
http://img235.imageshack.us/img235/6...diagramcn7.gif

Here's what I started with:
http://img224.imageshack.us/img224/1592/p1010232vz7.jpg
Pull the cap up to turn, push down to lock.
http://img224.imageshack.us/img224/4153/p1010233tm0.jpg

The arrow shows the air flow.
http://img224.imageshack.us/img224/2650/p1010238ro8.jpg

It only took me about 1.25 turns to change the boost pressure.
http://img224.imageshack.us/img224/9845/p1010239bq1.jpg

http://img480.imageshack.us/img480/5546/p1010240yn5.jpg

Don't forget these guys:
http://img480.imageshack.us/img480/6030/p1010241ls5.jpg

A6/Z6, LS/Vitaras
http://img480.imageshack.us/img480/4483/p1010242vv2.jpg

Ready to go
http://img480.imageshack.us/img480/5564/p1010251bz5.jpg

Intake manifold is the best source. Line goes to side port on wastegate.
http://img480.imageshack.us/img480/9894/p1010256vs5.jpg

Mounted in the engine bay.
http://img480.imageshack.us/img480/8417/p1010263ph8.jpg

Short hoses to mbc/wastegate vs. 2 5ft. hoses from in-cabin.
http://img480.imageshack.us/img480/3946/p1010268tl0.jpg

Open dump of course.
http://img480.imageshack.us/img480/6724/p1010270lj9.jpg

Here's some pics of the other beast:
http://img480.imageshack.us/img480/5518/p1010250cq2.jpg
175/70/13 madness. thin to win
http://img480.imageshack.us/img480/1779/p1010267bs2.jpg
DeluXe
http://img480.imageshack.us/img480/7151/p1010253rq2.jpg

I went from 9psi to 12 psi and it works great.
Next I'll install the motorola map sensor and up the boost/tune.
The red one will be basically the same, but the included T has a ball and spring inside. Stay Tuned for that.

An inline ball and spring mbc is so much easier. :y

Question/Comments/Concerns?

Re: Write Up: Boost Controller and External Wastegate top port w/pics
 

so the closed loop system prevents the surging, i didnt know that. Nice writeup Mike. do the turbosmart pieces look like good copies? let us know the difference when you install those.

Re: Write Up: Boost Controller and External Wastegate top port w/pics
 

So does the boost hold solid?

I had so many problems with the MBCs that I tried on my last setup. I tried both the TurboXS and Turbosmart MBC using a number of different configurations but never got the boost to hold like I wanted.

I never used the top port like you did though, maybe I will try that out this next time.

P.S. The real Turbosmart MBC is a combination of ball and spring and bleeder valve. The basic turboxs is just a simple bleeder valve.

Re: Write Up: Boost Controller and External Wastegate top port w/pics
 

Wouldn't closed loop be able to hold a given pressure during different air temps?

Re: Write Up: Boost Controller and External Wastegate top port w/pics
 

Yes, and that is the best part of closed loop system. It only relies on pressures. A bleed system relies on flow which is effected by temperature.

Re: Write Up: Boost Controller and External Wastegate top port w/pics
 

I use a real Turbonetics MBC.

Actually the Turbonetics MBC doesn't have a ball. It uses only a spring and diaphram. The nice thing about is that the diaphram has a vent built into it.


Be careful of some of the knockoff ones. They will have the arrow pointing the wrong direction.

Re: Write Up: Boost Controller and External Wastegate top port w/pics
 

And this setup does that? I'm lost.

Re: Write Up: Boost Controller and External Wastegate top port w/pics
 

Yes, it simply adds boost pressure to the top of the WG. How ever much you add to the top, you obviously need that much more on the bottom to raise the valve. Only pressures are involved.

A bleed system relies on flow to decrease the pressure to the WG and flow is related to temperature. Ideal Gas Law.

Re: Write Up: Boost Controller and External Wastegate top port w/pics
 

I'm having trouble figuring out how this setup works on pressure, while every other boost controller I've played with had issues of boosting different at different temps. We've still got the standard boost controller, and a wastegate with the standard spring in it. However it adjusts the boost, I'm having trouble figuring out how all of this eliminates the different pressures of different temps. ???

Re: Write Up: Boost Controller and External Wastegate top port w/pics
 

Anyone else had sucess with their MBC hooked up like this??