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Eleventeen
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297 Posts
Discussion Starter · #1 ·
Okay so the Spring mod was done on my car and now I have a boost problem.

1. My Profec-B doesn't work at all anymore...if it's 'on' it will just boost +20psi everytime.

..so I turned it off to see what the spring mod was doing

2. Spring mod with the profec off will hold at 15-16psi..most of the time. Sometimes it will spike or not work, but mostly holds to 15-16..

Any ideas why the BC isn't working at all or why the spring acts weird? I think I may just take this spring off to get my BC working again, and live with the boost creep in the higher gears...any experience from others is appreciated.

Thx
 

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The spring mod takes away some of the control of your boost controller. The spring physically pulls the wastegate lever in one direction while your boost controller is trying to move it in the other. By doing this you lose some of the fine tuning and you put a floor on the base boost level at a higher point than without the spring. What you can do is try a less stiff spring or stretch your existing spring.
 

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Eleventeen
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297 Posts
Discussion Starter · #3 ·
crossways said:
The spring mod takes away some of the control of your boost controller. The spring physically pulls the wastegate lever in one direction while your boost controller is trying to move it in the other. By doing this you lose some of the fine tuning and you put a floor on the base boost level at a higher point than without the spring. What you can do is try a less stiff spring or stretch your existing spring.
Hmm okay makes sense, the spring is too stiff then, if my BC can't do anything and it's not acting consistently. Do most people recommend the spring mod anyway? Seems like I might be better without it on, unless someone knows the exact spring that strikes the balance between adjustability and control? Is it the one from the FAQ?

Thx again.
 

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There is no FAQ for this mod. It's more of a hack and a matter of trial and error. Most use helper spring 29002 but even then results vary between cars because the tension will change depending upon where you bend the ends of the spring, plus the condition of everyone's wastegate lever may be different. You could attach an adjustable screw to the spring like Stu Hagen has. This can provide the ability to control the spring rate.
 

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Eleventeen
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Discussion Starter · #5 ·
Cool thanks, I'll have to test some things out. I see Stu's thread I suppose I'll read that too!
 

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Highway Demon
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2,898 Posts
i had the exact same problem and even after removing the spring i would have boost creep with the ebc on or off.. after looking into things further i had overlooked that the vacuum cap on the wastegate solenoid nipple that was facing downward was really old.. when i went to inspect it the cap was dried out and brittle and most likely leaking.. after replacing the vacuum cap my boost became consistant again, but i have not yet installed the spring mod again and have been driving w/o it with no problems.. boost holding all the way to redline.. this might or might not be the same problem you are having but i thought i'd share.. good luck

Brian
 

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good thread. i think i need to remove my spring because i have no control of my Hallman MBC plus i get boost creep. With the spring removed, will my MBC limit boost creep?
 
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