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(overspooled)
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Discussion Starter · #1 ·
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I have a 6 speed with stock twins
I have a greddy profec b Spec II.
Yes I have a bcc...
boost seems to taper off after 14lbs, sometimes i'll see a little more but its almost rare. Yesterday I tried to turn main boost and gain up to see if it would improve, so tried 70%, no change. If anyone has settings to share I'd be more than happy to try them. It seems like the warmer weather has had a huge affect. Last month
16lbs was petty normal for low settings...

I ordered a new BOV, HKS SSQV should be hear soon...I though my stocker might be leaking and well; any excuse to replace it

Any ideas of other things that could cause me to have low boost?
 

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Stock Twins King
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4,582 Posts
Pull your wastegate hose and do one pull, but watch your gauge closely. This in effect will give you the maximum boost your car can put out. If you still get low boost, then do the TTC temp mod. It really could be anything from a bad VSV to a vacuum leak. These are tough to research, but by no means impossible
 

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MTR said:
Do a vacume leak test and put on the spring mod while you are at it.
whats the spring mod?
 

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(overspooled)
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Discussion Starter · #6 ·
Thanks for the help, I'm going to give the spring mod a shot..hopefully this evening with work and all...I will turn the set and gains on my profec b to 0 so I can see what the spring is doing for me. I'd be happy with a consistent 17lbs...
 

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Space for sale
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gluck man

before you get down and dirty, check your connections with the boost controller
 

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(overspooled)
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Discussion Starter · #8 ·
yeah, that was the first thing I checked. Is this mod ok to perform in sequential? Most of the references are to ttc??? Not sure if I want to do that....
 

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Space for sale
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Morefaster said:
yeah, that was the first thing I checked. Is this mod ok to perform in sequential? Most of the references are to ttc??? Not sure if I want to do that....
Oh yeah!

I'm guessing the only reason why people would do it in TTC is because TTC will hold more boost till the end compared to sequential, but it would benefit you aswell.
 

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(overspooled)
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Discussion Starter · #10 ·
Completed the spring mod, For anyone that hasn't done this; I didnt have to remove anything, I just used some duct tape and a wrench. Tape the spring to the wrench, hook it on both ends (wastegate arm and water pump) and then cut the tape using a razor. 5-10min

The results; now I can build boost to 15.7 or so, but pretty hard to do a 4th gear pull to redline in traffic so playing it safe I saw 15.7 at around 5k This was with main boost set to 80% and gain at 75% <===seems a little high??? My goal here is 17lbs +-, I'm not trying to kill it

Tonight I will do the leak test. I tried it the old chgevy way with a little ether, but it probably is only leaking under boost if there is a leak... Time to get out the soup can!

Anybody use a hand pump? or a compressor at 15psi seem to do the job? How long should it take to leak down? I guess I'll pressurize until my boost gauge read 15psi...
any dangers I should be aware of???
 

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TRACK CAR
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Yea pressurize until your boost gauge reads at least 20-25lbs cause some leaks dont start until higher boost even though you only want 17lbs. The only thing to really be careful of is if you use a soup can to block off the intake pipe it can turn into a flying projectile if its not tightened enough. It helps if someone is holding/watching it for movement so you can stop pressurizing before it shoots across your garage.
 

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(overspooled)
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Discussion Starter · #12 ·
Nice, Hopefully I'lll have results this evening...Man Just noticed your in Gainsville. I mis FL I was born and raised there, but unfortunately my work has taken me to NM. Just got me thinking about how much I want to move back...
 

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TRACK CAR
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A good friend of mine moved out there a while ago working for the government. He is a car guy and says he can't wait to get back to FL. I think he isn't enjoying the high altitude with his turbo car.

Let us know how everything turns out.
 

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Discussion Starter · #15 ·
I definately need something,... Some yahoo in a supercharged z was almost gaining on me. I can't have that! Catch you later. (hopefully we can square up that tick for ya) 6:30 th soup can goes in hehehe
 

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Discussion Starter · #17 ·
I did the test, It looks like everything connected to the egr is leaking $%^& the VSV on the top rear of the intake plenum, looks like its holding, of oil in the lines though, not sure why ??
The two units behindthat, look like cans both seem to be leaking. I cant pressurize beyond 5psi w/o them bleeding. This doesn't seem normal to me. My poor twins must be killing them selves.... anyone else have this issue?
Sounds like time to remove egr???
 

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what kind of boost symptom do you have? what happens when you floor it in 3rd or 4th? does it hold and then lose boost pressure? for example, it would shoot up to 1.2 and then bleed down to 1 bar? let us know and good luck. hopefully you will fix it soon.
 

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iSketch Master!
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his profec reads in PSI, and he doesnt have a separate boost gauge yet. When we went to tune it was peaking at 14.4psi, and dropped to around 11.2psi. So we were barely even able to get to one bar normally. Dont think he has even been able to get up to 1.2bar lately.

Wel,l give max a call for those EGR plates though, and see if we can narrow it down some more.

Alex
 
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