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boost creep on aspec 4094 kit

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Old Apr 21, 2008 | 02:09 PM
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boost creep on aspec 4094 kit

I need to get this under control. I have had creep from the beginning on spring alone?? I lowered the spring to get 1 bar (on spring alone) . Seemed stable for sometime. Just the other day I saw 1.2 on spring alone (it was nice and cool out) ? While at the track this weekend I would get creep on every run. For example I would look at the logs and see desired boost level reached at 4800rpm (say 21psi) it would consistantly creep up until the shift. (say 1.5 bars) Would running a larger spring help regulate this? Running old school Profec B.
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Old Apr 21, 2008 | 03:03 PM
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When you say you were running it on the spring, were you running just a straight pressure source to the lower port of the wastegate?
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Old Apr 21, 2008 | 03:53 PM
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Originally Posted by arghx
When you say you were running it on the spring, were you running just a straight pressure source to the lower port of the wastegate?


I mean controller turned off. Ran as above before to confirm spring ratings.
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Old Apr 21, 2008 | 05:09 PM
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How do you have the controller hooked up? You should have the nipple on the compressor cover to the side of the wastegate. The top of the wastegate should have the line from your boost solenoid.
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Old Apr 21, 2008 | 07:03 PM
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Originally Posted by mono4lamar
How do you have the controller hooked up? You should have the nipple on the compressor cover to the side of the wastegate. The top of the wastegate should have the line from your boost solenoid.
Close but I do not have a nipple on my 4094 so I pull of the uim. I am 100% it is routed correct. Just not sure if its normal to be able to run above the spring rate with creep? I thought not. I can understand the Boost controller being not able to hold it dead on. So I was considering going with a 20+ spring and just run that but if I can not control the creep its not going to work. I will post a dyno pull showing boost being logged tonight.
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Old Apr 21, 2008 | 07:51 PM
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What size wastegate are you running? I know on our GT42 car here that we had bad boost creep and switched to a larger wastegate which cleared the problem.
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Old Apr 21, 2008 | 08:53 PM
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Originally Posted by Jason
What size wastegate are you running? I know on our GT42 car here that we had bad boost creep and switched to a larger wastegate which cleared the problem.

Tial V44.... ??
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Old Apr 21, 2008 | 11:05 PM
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So here is the dyno read out on hp and boost. Tell me what you think on the boost creeping??

https://www.rx7club.com/attachment.p...1&d=1208836783
Attached Thumbnails boost creep on aspec 4094 kit-dddy.jpg  
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Old Apr 21, 2008 | 11:55 PM
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had same problems when I had the wastegate line on the uim,

I taped in next to the compresor and have a steady boost now
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Old Apr 22, 2008 | 12:04 AM
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really. Then I will try that.. Whats the safest way to tap in? Buy a tap set? and fittings?
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Old Apr 22, 2008 | 01:19 AM
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Be sure to pull the compressor housing get the right bit i belive 1/8 npt nipple and clean it and blow out the metal shaveings!

Im running a 50 mil wastegate with a 20lb spring and its dynoed 3 times at 20.1 no spiking but when i had the 40 mil it spiked bad!

Oh, i would check for the best location for the tap before drilling!

Good luck.
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Old Apr 22, 2008 | 02:14 AM
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on the fd I used a fitting that came with a wastegate,

the safest is like busted7 said to remove the copresor housing,

few years ago on my lotus I used a plumbing fitting from home depot
and bought a single tap and drill bid for the size of the fitting,
did it with compressor in place, put a small rag in the housing, drilled it
and put grease on the tap bid worked good, never had problems with it

hope this helps
tony
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Old Apr 22, 2008 | 02:21 AM
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From: fort worth
sk8world

I am using gt4094r with .84 exhaust housing,
what size is ur housing?

sorry 4 asking off topic question
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Old Apr 22, 2008 | 07:08 AM
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Originally Posted by sk8world
really. Then I will try that.. Whats the safest way to tap in? Buy a tap set? and fittings?
You can just tap a spot on the intercooler pipe near the turbo. No need to tap the turbo.
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Old Apr 22, 2008 | 07:09 AM
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Originally Posted by sk8world
Tial V44.... ??
We switched to a Synapse 50mm wastegate which fixed the problem.
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Old Apr 22, 2008 | 01:10 PM
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Originally Posted by Jason
We switched to a Synapse 50mm wastegate which fixed the problem.

Jason, Never heard of this model? Is there a unit that will bolt right in to match the v-band on the 44 gate? was it this 44 tial you had issues with? I am going to try and tap of the IC piping as you suggested as I hate to tap into the comp. cover..


[Quote=tony94s4;]
sk8world

I am using gt4094r with .84 exhaust housing,
what size is ur housing?

sorry 4 asking off topic question [quote]

Tony, I have the .96 I ran the .84 and a 1.06 before on a base 40r and decided the .96 was the ticket for me.
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