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Discussion Starter #1
Okay i just put a downpipe on last night.

Prior mods, Greddy thrust manual boost controller, aikimoto intake, boost gauge.

Before the downpipe i could hit 1.2 (17.3psi ish) BAr ish for a while then the boost dropped to .75 bar (11.1 psi ish). I guess that was due to a ladck of a downpipe. I put the greddy manual boost controller fully open and I only hit 14.5psi. How can i get more boost? Is there something wrong? I don't get any boost spikes or anything it comes on perfectly smooth now.
However I haven't checked the boost when i am rolling over 85 mph. Or with the engine cold at all. This is slamming on it 15 times in a row 30-85 mph in 20 minutes. Or does the turbo just get weak when it's this hot. Tempterature 55-59 degrees. High humidity
 
Z

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boost leak.
when I have same modes as you without DP, I can only hit 14psi max. DP allows you to boost as much as you want, but your vacuum system has to be air tight! put some soup in a spray bottle and spry on vacuum hoses while the car is idling. then rev up the engine to try to find bubbles forming, if you see bubbles poping out, then you got a vacuum leak at that spot, change vacuum hose.,
 

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Discussion Starter #3
Hmmm well you see without the downpipe I coudl hit 1.3 bar and hold it for a while at times.. then it ususually dropped to 1.1 bar or .8 bar. Once I put the downpiep on it's solid but at 1.0 bar. Feels way more pwoerful but still. I'll try that in the next hour though
 

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Discussion Starter #4
Okay i checked the leaks, I sprayed soap water on all the pipes i coudl see. anyone know of a proper way in whcih one would check for boost leaks? thanks any comment woudl be appreciated,.
 

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breakemlose said:
Okay i just put a downpipe on last night.

Prior mods, Greddy thrust manual boost controller, aikimoto intake, boost gauge.

Before the downpipe i could hit 1.2 (17.3psi ish) BAr ish for a while then the boost dropped to .75 bar (11.1 psi ish). I guess that was due to a ladck of a downpipe. I put the greddy manual boost controller fully open and I only hit 14.5psi
I'm not sure if it's your terminology or what but having a manual boost controller "fully open" will not let you achieve maximum boost. To do this you must "fully close" the MBC.

I believe the Greddy works just like the Hallman MBC, a ball and spring system. The more pressure you put on the ball with the spring the higher the boost has to be to pop open that valve which then lets the wastegate open. The way you put more pressure on the ball is to close the knob, crank it down.

Either your MBC is not set correctly, you have a boost leak (check intercooler hoses closely) or the person who put the DP on screwed something up. Good luck.
 
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soup water is the best way. anotehr way you can check your hoses is to compress the whole system from your intercooler hose. however, a leaky vacuum hose can very easily be identified.
either its old and its hardened, or it comes off easily. just pull on each hoses is what I would do, if it comes off easily, than replace it. ALso, make sure you chec hoses on both the turbo side and intake manifold side (behind throttle body,...I found my boost leak there before)
like I said, I can burn my fingure trying to twist my vacuum hoses off, so anything looser than that should be replaced.
 

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a really good investment is Silicon vacuum hose replacement kit. I used the one from www.hosetechnique.com . I foudn some cracked hoses which were not at all obvious. The way to pressure test your system. get a plastic pipe end cap from a hardware store get a tire valve drill a hole in the cap. Stick the cap in the line going to the intercooler and pump up the system to 18 psi and then check for retention of pressure and leals with soap not soup;)
 
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