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adidasdudegst
05-19-2010, 10:38 PM
99 GST
- 3" full turboback
- 14b turbo
- VRspeed FMIC
- VRspeed 2G jpipe
- Greddy RS BOV
- FP Intake pipe w/ Amsoil filter
- hallman MBC
- walbro 255
- stock injectors
- Fuel lab pressure regulator

I bought a new 14b turbo and it didn't come with a wastegate, so i probably made a mistake by buying somebodys off of ebay. But the issue im having is that it doesn't seem like the boost controller is working, or the boost gauge is fd or the hose for the boost gauge is kinked. I have the 1 hose coming off the boost controller connected to the wastegate, and the other hose tee'd off on the BOV vacuum hose that goes to the intake manifold. The MBC is adjusted all the way negative, and the prosport boost gauge is showing the max boost on the gauge.

So is the boost gauge bad or hose kinked somewhere? or is the wastegate made for a bigger turbo and has an automatic opening for over 30psi? That obviously wouldn't make since, because i would think i would hit fuel cut if i were boosting anything over 20psiish with stock injectors.

viridionplague
05-19-2010, 10:45 PM
your wastegate isnt opening. you might have your hoses backwards.

asshanson
05-19-2010, 10:46 PM
Maybe your MBC is broken. Hook the wastegate directly to the boost source off the BOV and see how many psi it makes. Make sure that line isn't clogged or kinked.

If the boost gauge line was kinked it would show zero boost, but if the line to the wastegate wasn't working right it wouldn't open at all which is what it sounds like. Or you have a bad wastegate that doesn't work. You could probably take it off the turbo and have it pressure tested to make sure the arm moves at a certain psi.

adidasdudegst
05-19-2010, 10:59 PM
alright ill give it another look in the morning. i looked at alot of mbc drawings on forums, and the way I have it is the same.

If you have the MBC horizontal, the port coming off the end opposite the end of the the control knob, i have that connected to the bov line, and the port thats opposite that is going to the wastegate.

Thanks for the info!

n8kerns
05-20-2010, 12:50 AM
I have to agree that your WG isnt opening. Like Hanson said try hooking up straight to the WG and see if that gets it to open if not then it is your WG causing you the problems.

Also what kind of boost controller is it? If its not a regular ball and spring type there could be more to it. If it is then you could also try hooking it up to the nipple on the jpipe (if there is one) instead of making a tee from your BOV.