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Discussion Starter #61
It's a good video. There is absolutely no reason to have to do this on stock turbos for our cars though. There is no way a 9b exhaust blade can flow that much exhaust to cause this unless there is a defective wastegate or actuator.
 

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Money pit owner.
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Theoretically, due to the inherently restrictive nature of the 13g/9b hot side exhaust housing - very small diameter, a free flow exhaust should be enough to cause boost creep, "Meh, that wastegate port is to tiny/restrictive, I will just continue through the compressor housing since there's no precat slowing me down"
I''m also guessing that a larger turbo's (15g/20t ) wastegate port is larger and better flowing.
That's my theory anyway. :)
 

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Discussion Starter #63
My boost creep issue was pretension. I had to loosen pretension 6 full turns. I'm curious to see what yours ends up being.
 

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Money pit owner.
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With winter in full swing here and my car up on jackstands, there will be no boost creep testing till end of march :(
My 9bs are untouched since factory install, I could reduce preload, it seems to be a bear to acess the rear adjuster.
 

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Discussion Starter #65
Just another update. I thought my problem was resolved but I still have the same damn problem. I think I just need to throw the 15g's on there and call it a day. I must just have an inefficient set of 13g's that don't want to hold more than 13psi. Only way i can hold more than 13 to redline is to make the wastegates so tight that it creeps up. I just lost to an IS-F on the freeway....embarrassing...
 

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Really old gear head
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Pretty sure stock pretension on wastegate actuator is three full turns after the adjuster is set to snuggly (a Trump term maybe :0) fit over the actuator lever. Of course, then pressure test both turbos together to see that they open at the same time and possibly make minor adjustments.
 

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Discussion Starter #67
Pretty sure stock pretension on wastegate actuator is three full turns after the adjuster is set to snuggly (a Trump term maybe :0) fit over the actuator lever. Of course, then pressure test both turbos together to see that they open at the same time and possibly make minor adjustments.
Hey guys, it's been a while and I just wanted to give an update. I ended up upgrading my turbos to 15g's which still did not resolve the issue but rather made it worse. Now I can only hold 11 psi to redline. Someone told me it that the problem can be my tune. I'm pretty much out of ideas.
 

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I did not see it mentioned, but what are the settings in your AEM Tru-Boost gauge controller? They work well within reason, but they are also known to either spike more or cause slightly slower spool depending on the balance between 'SPr" and "DC"... also, did you opt for stock TD04 turbines on the 15G's, or did you have them upgraded?
 

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Discussion Starter #69
I played with all the settings and I've also used an MBC to rule out the controller.
 
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