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Discussion Starter #1
Just received MBC today, only didn't come with any fitting instuctions, i don't know which way round the R-W-C pipes fit on to the MBC, any help would be great, thanks

Lee
 

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Assuming the MBC is T shaped, the C and W pipes connect to the horizontal arms, and the R to the vertical lie this:

C=[]=W
....[]
....R
 

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Discussion Starter #3
cheers MarkE
, MBC is now fitted and the power delivery is much different, before the MBC was fitted the turbo used to cut in much earlier and well i'd say that it boosted for longer
, now the turbo takes longer to engage and quite alot of responsiveness in lower revs has been lost, yes i have maneged to get alittle more boost with the MBC fitted but does this mean i sacrifice initial accelaration for alittle more boost? now she just seems to be well sort of dead in the water untill the turbo kicks in
should i just replace the dodgy automatic boost control valve or is there a simple solution for this?
 

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something is not right ...
Mbc's usually get the boost going far earlier and hold on longer (you can get overboost spikes )
so what you are getting is the opposite of what is expected
Hve you checked your wastegate actuator ?
double checked your pipes ?
 

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Discussion Starter #5
the hoses are connected the way MarkE has posted above, i suppose the C + W hoses could be the wrong way around
i have connected with the locking screw at the front, it could be the wrong way around? i have had a look in the wastegate area and all seems ok although i will double check in the morning
 

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c and w hoses connected round the wrong way should not be a prob...

In "normal" applications there is a hose going from the compressor © to the wastegate (w) so as long as they are connected its ok...
you should be able to blow through the mbc between the c and w
The mbc bleeds off some air to (r )which is controlled by the bleed screw..
hth
 

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Discussion Starter #7
checked the wastegate, all is ok on that front, could it be the case that the abbott apc box just delivers the power better than the MBC?
 

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does not work that way...
Ecu determines how it works
Apc is one component which the ecu controls the wastegate.
the mbc if fitted as you have takes this control away

try this
reconnect the APC as it was
break into the tube going to the wastegate (w )
put the mbc in the line leaving the rightangle tube unconnected
In this way you are bleeding some of the air away from the wastegate
Carefull now... start at where it seems normal ie valve shut ,and increase slowly from there.
It only takes a little bleed off to make a difference
If you get into overboost protection (feels like hitting a brick wall ) back off the mbc towards its origonal setting...
You will have to do this a few times till you get it right
good luck
 

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I totally standby what Ylee says. When I bought my MBC from Elkparts, Justin told me to do exactly the same. By fitting the MBc like this, you are retaining a degree of protection afforded by the APC rather than cutting it out altogether.
 

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Discussion Starter #11
after plumbing the mbc in several ways the carly is still suffering from loss of power, especially at lower revs, i assume from earlier posts that the problem could be with the wastegate actuator can any one confirm this? any help checking and replacing the actuator would be great.
 
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