manual boost controller take 2

[mickster8888]

ok guys here i go again. i got an original manual boost controller 935 style and have been going crazy trying to get it to work. i've tried every combination of hook up configurations and the only one that kinda works is when i leave the top port on the wg vented and tee into the line btween the intercooler and wastegate. the only snag is i have to close the controller completely to get the lowest boost level- .6 bar. i have a .47 bar spring from a 924t. can anybody tell me what i'm doing wrong? i've also tried to connect the line from outgoing side of controller to vent port of turbo but that didn't work as the boost would go to 1.2 bar with the controller threaded in or out. any help would be greatly appreciated. thanks in advance, mick

[mickster8888]

anybody got any ideas?

[Miguel Antonett]

If you haven't figured it out yet, there are some good dicussions/threads ongoing on that matter as we speak.

[Porsche 935]

One boost reference line goes to the port on the side. This is the normal configuration for spring only. If you add a controller you need another line that goes to the controller and from there out to the top of the wastegate. The controller takes a portion of the boost air and applies it against the other side of the diaphram to allow more boost than the spring will normally hold. Hope this helps.

[timspu]

Originally Posted by mickster8888

ok guys here i go again. i got an original manual boost controller 935 style and have been going crazy trying to get it to work. i've tried every combination of hook up configurations and the only one that kinda works is when i leave the top port on the wg vented and tee into the line btween the intercooler and wastegate. the only snag is i have to close the controller completely to get the lowest boost level- .6 bar. i have a .47 bar spring from a 924t. can anybody tell me what i'm doing wrong? i've also tried to connect the line from outgoing side of controller to vent port of turbo but that didn't work as the boost would go to 1.2 bar with the controller threaded in or out. any help would be greatly appreciated. thanks in advance, mick

I have a manual boost controller fitted in the engine bay and i have it connected the same way as you do to give me 0.9 bar. I also have a standard wastegate set up. Mine is now fixed at 0.9 bar.
I need to access the engine bay to adjust it.
My boost controller has a ball and spring set up so intercooler air pressure has to overcome spring pressure to get the waste gate to open.

Porsche 935, What are the benefits of controlling pressure into the vent rather than the boost connection?

[Porsche 935]

If you release all the pressure to the vent area from the controller then you get whatever pressure the spring is set for. I can go from .8 bar to 1.7 bar with a twist of a knob inside my car.

[TurboKraft]

Precise control, more stable boost pressures i.e. less fluctuation after it opens.
Imagine you're adding some damping effect to the wastegate valve.

[timspu]

Is it possible to get a schematic of how the install would look.
Obviously my set just delays pressure getting to the spring. Would be interested if i can set my MBC to achieve the same desire, this would also help original poster
Thanks

[onboost]

Originally Posted by timspu

Is it possible to get a schematic of how the install would look.
Thanks

Not the greatest diagram/schematic.. but you get the idea.

[JFairman]

I have the same one in my car that onboost posted above. It works great and you can usually buy the kit on ebay for around 25 bucks.
I mounted the regulator in the metal cover under the carpet that covers the shift coupler in the back of the center tunnel.

The regulator fits good there a little over to the right side of the car because the shift rod takes up the space in the middle under there.
I made a round hole in the carpet about an inch wide for the regulator knob to poke through and can reach back from the driver seat if I want to adjust it.
I leave it at 1.1 bar with 93 octane Florida pump gas and water methanol injection that comes on at about .7 bar

Here's a couple ebay manual regulator types that connect to the top port on the wastegate. They work well and fit in the shift coupler cover if you want it inside the car.
I ran the 2 hoses through a hole I cut in the rubber bellows over the transaxle shift rod coupler at the back end of the center tunnel.
http://www.ebay.com/itm/BLACK-T2-UNIVERSAL-ADJUSTABLE-MANUAL-GAUGE-TURBO-BOOST-CONTROLLER-1-30-PSI-JDM-/261102936706
http://www.ebay.com/itm/Turbonetics-Manual-Boost-Controller-Honda-Civic-Toyota-Subaru-WRX-STI-EVO-/231188927068

[timspu]

Brilliant. Thanks for posting the schematic.