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Alpha Racing
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Discussion Starter #1
I recently purchased my MKIV twin turbo. The Car already had the temporary TTT setup and the bleeder mod. The car was boosting 19lbs. at second gear and 22lbs. at 4th. I decided to put in a manual boost controller to bring down the boost level. After installing it i tried it out and the car would still boost 19 at 2nd and 22 at 4th. So, my friend and i decided to put the car back to stock by taking off the bleeder mod. Well, i took it out for a drive and it was still boosting the same numbers. Does anyone know what the problem could be? is my wastegate staying open? I still have the True TT temp. setup. Could it be that the check values are messing with the vaccum? Any ideas would help.
Another problem is that when i would be in gear and floor it it would sound like a vaccum cleaner... and the car would not boost, but then when i would downshift the car would boost up really quick. thanks...
 

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your boost guage is fubar our cars do not make 19 psi in 2nd with stock turbos and I am told although I ahve never tried it that the stock turbos top out at about 20 psi. be real careful with guages I melted a # 2 tubo while tunig to a bad gauge.
 

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all the more reason I recently got an autometer gauge and it turned out to be wildy inaccurate.... ii trustes it and killed my 2nd turbo. I would get rid of it might see if it is still in warranty or jsut go buy something else. Alternatly see if you can borrow a friends gauge to see if you get a different reading.
 

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Super Moderator!!ON PATROL ALL OVER!!
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best boost guages out ,greddy ,hks ,apexi or defi

im getting a new apexi electical one, im going to be selling my hks manual boost guage soon if you want to buy it email me !
 

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Alpha Racing
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217 Posts
Discussion Starter #6
Turbo Topping out?

From what you said about turbo's topping out at 20lbs. It wouldn't be the turbo, the wastegate would top out. But regardless if my gauge is fubar, giving an estimate it is still boosting high on second gear. There was another post that a guy was claiming that he was boosting 25lbs. I'm pretty sure that boosting high can be done, but can mess up the turbos. I'm looking for a way turn the boost down on the street, but i already tried installing a boost controller and didn't work. I thought i was because i was running the TTC. Anyone know why i can't control my boost?
 

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Re: Turbo Topping out?

Frankie Five said:
From what you said about turbo's topping out at 20lbs. It wouldn't be the turbo, the wastegate would top out. But regardless if my gauge is fubar, giving an estimate it is still boosting high on second gear. There was another post that a guy was claiming that he was boosting 25lbs. I'm pretty sure that boosting high can be done, but can mess up the turbos. I'm looking for a way turn the boost down on the street, but i already tried installing a boost controller and didn't work. I thought i was because i was running the TTC. Anyone know why i can't control my boost?
yes you could have a bad waste gate I am not sure how you hooked up your boost controler that could be an issue I saw the other post about high boost and As far as I know the stock turbos are incapable of producing more than 20 psi and are absoluty incapable of doing it in 2nd gear tTC or not. The do not flow that high and are limited by design which is why people buy single turbos
 

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Alpha Racing
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217 Posts
Discussion Starter #8
IC....

well, today my boost gauge hit 24lbs. That's from reading the autometer... My car is getting some funky boost... In regards to the boost controller. I was running a manual XS engineer boost controler...
 

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one other thought check your waste gate it may be totaly disconnected look at the bottem of the gate actuator( the waste gate itself is inside the turbo) and check to see how the hoses are hook up and capped. check out the page on mkiv.com about the blitz dsbc install for pics
 

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The stock turbos will boost higher than 20psi in second and considerably higher in the higher gears. I have easily hit 23.5psi in 3rd gear. I would check you connections to the wastegate. Make sure you have one of the fittings on your actuator capped. the other fitting should go to your boost controller. Even after you get your boost controller hooked up correctly, you will still see about a 3psi difference from 2nd to 3rd. Hopefully you will have it down to about 15psi in second and 18psi in fourth.

Later, Steve
 

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Alpha Racing
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217 Posts
Discussion Starter #12
Ic...

Well that's exactly what i did. It didn't work though. I closed the valve on the boost controller and it was still boosting the same. So my friend said that maybe my wastegate is wide open and isn't closing, cause now i put all the vaccum hoses on took out the bleeder and it should run stock but it isn't still the same. I did do the temp. TTC you think the vaccum could be messed up?
 
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