Manual Boost control on Fleabay

[CJay]

I've fitted the R-spec MBC and it works fine, you don't need any other piece of kit apart from the MBC itself (and 2 cable ties).

I originally has it set at 12psi but have recently turned it down to 10psi due to fuel cut (problem solved).

As per the other responses, fit a boost gauge first and foremost and get used to the stock boost pattern. Fit the MBC fully closed and find a clear section of road where you can pull in and out of. Gradually (2 turns at a time) turn it up until you reach the desired boost level (12psi is a good mark to aim for). A half an hour of spirited driving should see you good in terms of getting the boost level right.

CJ

[aboo]

I've fitted the R-spec MBC and it works fine, you don't need any other piece of kit apart from the MBC itself (and 2 cable ties).

I originally has it set at 12psi but have recently turned it down to 10psi due to fuel cut (problem solved).

As per the other responses, fit a boost gauge first and foremost and get used to the stock boost pattern. Fit the MBC fully open and find a clear section of road where you can pull in and out of. Gradually (2 turns at a time) turn it down until you reach the desired boost level (12psi is a good mark to aim for). A half an hour of spirited driving should see you good in terms of getting the boost level right.

CJ

Should'nt it be fully closed then open it?

[CJay]

Should'nt it be fully closed then open it?

Actually, I think you're right - post amended.

CJ

[Roberto]

Again confusion reigns....

I would have said that it was installed Fully Open and then turned down 1/4 turn at a time and slowely set up that way, checking the boost each time.

Gone to find paperwork that came with MBC.

Found it!!!

I Quote: " To adjust the "R-Spec" valve, slcken the lock nut, then turn the knurled adjustment screw clockwise to increase boost and anti-clockwise to decrease boost. This should be done in small increments (1/4 turn) until the desired boost is achieved" End Quote!


Clockwise is tightening it, Righty Tighty Lefty Loosy!
This for the R-Spec boost Controller, that I have fitted.

[Roberto]

It is very important to install and set-up any mods correctly.

If you are not sure, ask the wuestions untill you are sure.
If still unsure get someone who is to do it!

[Kenneth]

If you are getting fuel cut below 14psi of boost

a) Check you don't have a pod filter
b) Check your plugs, you could be getting misfire rather than fuel cut.

[Subaru ETA]

at the dyno day i reached 15.7 psi using a turbosmart MBC and didnt get boost cut. I have seen my gauge get around the 17psi mark on a cold night.

as ken said, if you have a pod filter its going to act retarded. we saw on our recent dyno day one member had a Pod filter, custom pipe work etc and i think he only got in the 160kw ball park. my car with std intake system (bar a k&n panel filter) plus 3inch exhaust headers back got in the 180kw's

[ianturbo]

If you are getting fuel cut below 14psi of boost

a) Check you don't have a pod filter
b) Check your plugs, you could be getting misfire rather than fuel cut.

no pod filter and new ish plugs ....... better have a look at the gap !!!below 10 its ok anything above . not good
ian

[Kenneth]

What brand plugs you got in the car? Am working on a theory that Denso are crap in the VR-4s

[ianturbo]

they werent denso ???
iridium things spring to mind ! back ones were flat at a witches tit but front ones were new !! lazy tw#@ts !
aint sure what i gapt them at though !
ian

[Kenneth]

What is your fuel economy like?

Could be a boost leak that only shows up above 10psi.

[ianturbo]

It ain't good but it never has been , i just fill up when empty ,
all clips on the pipes seem to be tight ,could the bov be a bit knackered ? its the plastic one , i have never bothered with it since i got car 18 months or so ago ??
ian

[elnevio]

Could be.

Have a hunt around on MLR for an EVO VIII plastic one. They're always swapping theirs off for better (well, noisier!) items. They're a direct swap for our BOVs and should be able to get one for about a tenner. I did, although my original was apparently working perfectly.

[Wodjno]

So ,is this why i get fuel cut at only 10/11 psi ?? better blank the T piece off then
ian

10/11psi but at what RPM ?

Is that at low revs, Hi Load ? Upto 4500-4750rpm at WOT ?

If so.. Thats fairly normal.. I used to get the same on Manual Controller.. I got round it by only giving upto 70% throttle until past 4750 RPM..

Also these damp cold conditions will see fuel cut more apparent

[ianturbo]

around 3500/4500 , usually in 3rd , and only if i am givin it a bit ,if i am gentle on the throttle it don't seem to do it ,
I'll have a look for anothe bov , don't want a woosh thing so standard one or evo 8 one .
thanx
ian

[aboo]

Fitted my boost gauge on Tuesday & its been sitting at 9psi on full throttle & 30 vacum since so going to fit mbc this weekend looking forward to noticing some diffrence

[ian_gelder]

Hi guys,

Glad the sites back up and running because I've been trying to fit the MBC and the gauge. I've got the tube running to the dash and to the engine bay, it's just that I'm not quite sure where to fit the T-Piece. Also could you make sure I've put the MBC in the right place?

I've uploaded a picture for you to mock

http://img101.imageshack.us/my.php?image=mbcra8.jpg

Is this the right way round and where should I put the T-Piece?

Thanks for your help

[MPBVr4]

Installation looks OK. Pressure source to bottom of the controller.
Take your gauge tapping from the back of the inlet plenum.
Pic courtesy of Brenmc's excellent article. (Yours will go to the gauge not a pressure transducer)

[aboo]

I just fitted my mbc & its fully open hitting 20psi so its of again. No more threads on the screw.

Doing 3rd gear runs full throttle hits 20psi then fuel cut. jumps in to 4th & drops to 18psi.

Anyone had this prob?

[miller]

I just fitted my mbc & its fully open hitting 20psi so its of again. No more threads on the screw.

Doing 3rd gear runs full throttle hits 20psi then fuel cut. jumps in to 4th & drops to 18psi.

Anyone had this prob?

Yeah my MBC has run out of threads, cannot reduce anymore. sitting now at 12psi but spiking to 15psi which is producing CUT or wasted spark at 4.5k rpm.