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Old 08-28-2007, 07:26 PM   #1
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Default Boost creep- Only when hot?

I recently installed a new turbo kit with a Garrett T2560 on my '96. I've been working out all the kinks and the one that has me baffled is boost creep. The external wastegate spring is set at 9.5 PSI. and it holds very nicely about half the time (in all gears.) The other half of the time I can see the boost creeping up to 11+ PSI and from what I can tell this only happen when it is hot out. Would a boost controller be a good idea to solve this issue?
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Old 08-28-2007, 07:37 PM   #2
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a MBC allows the air not to travel to the wastegate until the very last time. This allows for faster spool up because the WG opens gradually as it nears it's limit. It's a good investment and only 15 dollars. Give er a shot. I don't think it'll solve the problem though.

What is your setup?
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Old 08-28-2007, 08:18 PM   #3
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your problem is the WG is not venting enough to keep the psi stable where you want it. A MBC will allow you to stabilize this at a higher rate, but ultimatley you will need to look at the issue of flow where is the EWG placed on the manifold and how much flow can it support ie is it pretty, smallish before it rejoins the DP, where are you sourcing the boost signal? and what springs have you tried in there?
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Old 08-29-2007, 04:06 PM   #4
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I have a BEGI series 3 system and the boost signal is coming from the compressor housing. I haven't tried different springs.

The main thing that I don't get is why it holds great half the time and not the other half. If it were an issue with the wastegate not flowing enough wouldn't I have the problem all the time? Would a leak between the compressor housing signal and the wastegate also cause this issue?
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Old 08-29-2007, 05:22 PM   #5
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If heat is the variable maybe the actuator rod or the flapper are expanding and binding?
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Old 08-29-2007, 08:36 PM   #6
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Quote:
Originally Posted by PAT! View Post
If heat is the variable maybe the actuator rod or the flapper are expanding and binding?
<--- My guese to, it's worth a look.
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Old 08-31-2007, 12:50 PM   #7
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I put zip ties over the vacuum lines and it seems to have fixed it. I can't say for sure because I don't see the issue all the time, but I'll report back.
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Old 09-04-2007, 01:39 PM   #8
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Just wanted to report back to say that the zip ties totally fixed my problem. Funny thing was that I put zip ties on all my lines except the one from the compressor and the wastegate. Got to love those 25 cent fixes!
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Old 09-04-2007, 04:51 PM   #9
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Zip ties all over? Phillip loves you.
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