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Fitting a bleed valve...


scooby_doo_do

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  • 10 months later...
Please can you post a pic or diagram - I dont know what pipe to plug my MBC into.

Ian C provided some really good TT hose piccies. Is the hose on one of these piccies ? :respekt:

 

hope this helps:-

 

I've just fitted this MBC to my standard Jspec:-

 

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&rd=1&item=7960792764&ssPageName=STRK:MEWN:IT

 

If you look between the fan and the front of the engine on the left hand side you'll see the pipes shown in the previous picture by "Supra TT myster". This picture shows Hose 2 (the one on the right) which has been cut and a T bar attached - ignore this as you'll be putting your MBC there instead (unless you want it routed into your dashboard)

 

I come across a problem with my MBC, even with the screw fully tightened there was no change in boost still at 0.6 bar. Out of curiosity i tried it without the pipe on (very stupid i know) and i hit fuel cut in 3rd at 1.2 bar so i come to the conclusion even with the screw fully tightened it was still restricting the air flow so i used a very small drill bit and made the hole larger. This done the job as i could now adjust the screw so that boost settled on 1.0 bar. :)

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yes it does but nothing major. You can certainly hear the whistle of the turbos more now and the tone of the exhaust has changed.

 

It did fix another problem i had tho - before if i dropped down from say 4th gear to 2nd and if the revs stayed above 4,000 rpm, sometimes the #2 turbo didn't spool up at all - now i don't have that problem so overtaking slow vehicles down country lane is far safer.

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yep - either cut the hose in half and stick the MBC in the middle

 

or unplug one end stick the MBC in the pipe and add a new bit of pipe on the other end.

 

Find a big empty bit of road (you're be going silly speeds whilst looking at the gauge not the road!) you'll need to pull over at each end and adjust it. They say 3rd gear is the one use for setting it up but i found 4th best.

 

when testing it remember things get fecking hot down there and turn the engine off first as the fan hurts when you bash your fingers on it !!! (take it from me) :cry:

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http://www.mkivsupra.net/vbb/attachment.php?attachmentid=13234

 

Hi, see where the red arrow is pointing

 

that’s the hose that you need to connect the bleed valve to. Get your self some hose- fuel hose is good. A few clips to hold the hoses is place.

 

Take the hose of the wastgate and connect it to the bleeder. Attached a 2 inches hose to the other side of the bleeder- the attached the end of that hose back to the wastgate.

 

When the bleeder is closed you have a stock set up. As you open the valve the boost will rise

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yep - either cut the hose in half and stick the MBC in the middle

 

or unplug one end stick the MBC in the pipe and add a new bit of pipe on the other end.

 

Find a big empty bit of road (you're be going silly speeds whilst looking at the gauge not the road!) you'll need to pull over at each end and adjust it. They say 3rd gear is the one use for setting it up but i found 4th best.

 

when testing it remember things get fecking hot down there and turn the engine off first as the fan hurts when you bash your fingers on it !!! (take it from me) :cry:

 

thanks steve - done it - youre right 4th gear is best - I can get a max of 0.9 bar in the warm weather :tongue:

cheers for the advice

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In the cold i was getting 1 bar (decat pipe)

Recent warm weather went down to 0.8 bar

Fitted the MBC and it went up to 0.9 bar fully maxed

Then I read Suprasteves comments on making the hole bigger.

So I did, and got out my trusty Black & Decker.

Whoopie presto, 1.0 bar most of the time with a short max at 1.1 bar in 5th

 

SUPRA STEVE IS A GENIUS :D :D

 

ardasaliah thanks for your pic - very helpful mate :)

 

footnote to other attempters: The end of MBC with the hole goes to the wastegate end (and not the other way round as I found out :read: )

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hmmm. is that all?

 

my uk spec is standard, other than 3" full decat, and I hit ~14 psi. Max ever (spike) has been 14.7psi, most common is 13.7psi.

 

don't ya wanna go higher? Will these MBC's not allow you to?

 

Ive only got the rear cat out. If you widened the MBC hole you would get more boost but 1.0 bar in this temp is a safe bet. In the cold it would go upto 1.4.

(As my car pre-MBC lost 0.4 bar from the freezing days we had to when the weather got warmer; I assume that the MBC'd car will gain 0.4 bar in the freezing cold)

Disadvantage of the MBC is that you would then have to open up the bonnet to wind down boost on freezing days to a safe J Spec Ceramic Stock 1.2 bar.

 

1.0 BAR IS 14.5 PSI

1.2 BAR IS 17.4 PSI

:eyebrows:

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Right got it today and fitted it, just turned the screw a quarter in and I was getting 1.05 bar!! Car felt very responsive and the turbos seemed to come on better. The big issue was that the car felt like it was hesitating or jerky once it peaked at 1 bar ish?? Is this early sign of fuel cut, restriction caused by both cats or is it the fuel pump not up to the job??

Anyway I then turned the screw anti-clockwise(out)so it was barely in the valve itself. Went out for another run and got 1.2bar!!!!! eeek!! Car felt again jerky over 1bar, but im left wondering whats happened to the fuel cut??I thought turning the screw out/anti-clockwise would decrease the boost not increase it?? Could the large levels of boost be down to the diameter of piping im using to plumb it into the acutator?

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SEEMS A LOGICAL ASSUMPION - spring must need some tension

I had the opposite problem and max at 1 bar which I am delighted with as I never plan to go above as poof tubbies = £1500

try extending the spring a little then re-inserting (not ideal)

 

PM me if you want one of my MBCs as I would be interested to hear of the result

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