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Discussion Starter #1
I have a 92 hatch with a 306 stock block and an ON 3 70mm Kit. Took her to the tuner last week. I'm scared. 524 HP and 527ft# at 5500 RPM. But.... I am having serious boost creep issues. I cant keep the boost down with only the yellow spring in the gate. She stays at 5 psi until about 4500 and then creeps to 8-10. With my combo this is translating to easily over 500hp and we know what that means. Also, I'm running 42# injectors and I'm running out of injector. Anybody else having boost creep issues with the ON 3 gate? And does anybody have a gate with a 4 bolt flange like the ON3 comes with? I saw the tial F40, F41, F46. Anybody have one for sale. Also need some 60# injectors.
 

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im pretty sure guys are running manual boost controlers to control the boost levels.
 

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Search and you will find a recent thread started by firemanwill. He had the same problem when he installed his On3 kit.
 

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Discussion Starter #4
im pretty sure guys are running manual boost controlers to control the boost levels.
I've got a manual boost controller. Which ADDS boost to the car over and above the spring pressure which does nothing at all to limit boost. Plus it is bypassed right now which puts it out of the picture as far as the problem goes.
 

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What are you using for a vac source for your WG? Some people who have had boost creep have tapped the turbo discharge for a vac source to the wg and eliminated the problem. Others have had to upgrade to a larger wg or even add a second. My friend installed an On3 kit he purchased from from me, installed it on his car w a nearly identical combo and had boost creep I did not. We tried everything even swapping my wg and bov to his car. Nothing worked so he had a second chinese ebay bov installed and the problem was solved.
 

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Discussion Starter #6
fmyth- wg vac source is at the intake. I thought about tapping the turbo and still may.I wrote your write up on your friends car boost creep. I think that the diaphragm may be leaking in the wg? I was just wondering if anybody else is experiencing this same issue. I think its time to go with a bigger better gate.
 

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fmyth- wg vac source is at the intake. I thought about tapping the turbo and still may.I wrote your write up on your friends car boost creep. I think that the diaphragm may be leaking in the wg? I was just wondering if anybody else is experiencing this same issue. I think its time to go with a bigger better gate.
u need a boost refrence source between the turbo and in front of the throttle body most the china turbos r not taped so tapping the cold pipe from the turbo to intercooler is what most do should help with your problem
 

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Discussion Starter #10 (Edited)
OK, drilled and tapped the turbo discharge and I'm still having the same problem. Boost continues to creep. I am beginning to think that the WG is the culprit. :confused:

Does anybody know of a gate that will match up to the ON3 flange? Looks like an F46 Tial has the same flange as the ON3 but I wondered if anybody matched one up for sure. If not I will just buy a gate and weld a different flange.
 

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Discussion Starter #12
r u puting that vac source to the side of the wastegate and leaving the top one open
absolutely. however one more thing I need to check is to make sure the bolt in the banjo fitting is clocked so that it sees boost correctly. however, I thought that if you look at the banjo fitting that it didnt matter which way the bolt went because the inside of the banjo fitting is grooved so that no matter which way the bolt goes the gate will see pressure. somebody chime in if Im wrong. I looked at it before I put it on thinking the same thing but I will pull it and recheck.
 

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If its creeping it means you need a bigger wastegate or better routing of the exhaust. I would just step up to the next wastegate size.
 

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the boost creep is caused by the reference line being behind the throttle body. the best place for boost reference for the wastegate is the dicharge on the compressor housing. i had to add a brass barb fitting to my T70 for a boost reference...my car holds a rock solid 8 psi with no spike or creep..BTW, i have the 4 bolt 46mm WG
 

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Discussion Starter #17
the boost creep is caused by the reference line being behind the throttle body. the best place for boost reference for the wastegate is the dicharge on the compressor housing. i had to add a brass barb fitting to my T70 for a boost reference...my car holds a rock solid 8 psi with no spike or creep..BTW, i have the 4 bolt 46mm WG
See post #10.
 

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the boost creep is caused by the reference line being behind the throttle body. the best place for boost reference for the wastegate is the dicharge on the compressor housing. i had to add a brass barb fitting to my T70 for a boost reference...my car holds a rock solid 8 psi with no spike or creep..BTW, i have the 4 bolt 46mm WG
Not exactly. With better TB's and good intercoolers the pressure difference between the two is usually very minimal. Plus when you creep your valve is tapped out and can't lift any higher. More pressure won't lift it any higher. Flow is the problem. With most WG's just the positive pressure form the turbo and the lack of vacuum from the intake help the diaphragm live longer because it is only pulled/pushed in one direction.
 

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Not exactly. With better TB's and good intercoolers the pressure difference between the two is usually very minimal. Plus when you creep your valve is tapped out and can't lift any higher. More pressure won't lift it any higher. Flow is the problem. With most WG's just the positive pressure form the turbo and the lack of vacuum from the intake help the diaphragm live longer because it is only pulled/pushed in one direction.
the best boost source will always be the ones closest to the boost producing unit..if a 46mm WG is creeping on such low boost then there is something wrong for sure. before buying another gate id check the gate with a specific spring on a bench with an air compressor.
 
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