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Old 11-12-2003, 12:15 PM   #1
pierceman
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Default will vf22 solve boost creep? HELPPPP

ok this is getting silly, creep, every time I drive. I'm catless, hks dp, 3" all out. I have read about the jimmy rig solution and don't like it. I know there is no utec or reflash out yet, and I don't want to prt the wastegate, but this has to stop. Do I go back to stock DP till the ecu is upgraded? Or will a vf22 solve all my issues????? Help me please, I'm still a NEWB. But did not like the search results.....

Thanks
MAtt
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Last edited by pierceman; 11-12-2003 at 12:58 PM.
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Old 11-12-2003, 12:31 PM   #2
DISCOPOPE
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by jimmy rig you mean wastegate porting?
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Old 11-12-2003, 12:58 PM   #3
pierceman
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no, I meant the electronic rig where you go in and clip here and splice there to fool the computer. I have looked at the wastegate port, but would prefer to just buy an upgraded turbo so I can switch back if need be.

Is it better to have the wastegate ported or better to get a vf22, or am I way off?

thanks
MAtt
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Old 11-12-2003, 01:44 PM   #4
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Sorry, I'm just looking for a basic kind of answer, will a vf22 by its self solve the creep? or do I need more?

thanks again
MAtt
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Old 11-12-2003, 01:52 PM   #5
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I am guessing you might have boost creep with the VF22 since it still is a VF series turbo. Get yourself a good EBC and/or porting or go back to stock downpipe.
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Old 11-12-2003, 02:36 PM   #6
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what about hks external wastegate? i see that ultimate put one on their stage 3 in addition to the e-manage.

ive thought about getting a turboback and a a ported turbo swap. but then i start thinking about all the other stuff that should be installed at the same time and i feel like screw it.. ill run stock untill spring.
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Old 11-12-2003, 02:38 PM   #7
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Boost creep has been a continual problem on STi's for a long time, guys on scoobynet have been battling this issue for years. You might want to check out that site to see if they have any solutions.
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Old 11-12-2003, 02:45 PM   #8
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Old 11-12-2003, 03:33 PM   #9
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When you guys say boost creep, do you mean boost is increasing as the rpms increase or are you saying boost is higher in higher gears?

On my car, I could never hold boost to redline with the stock turbo and boost in higher gears was higher but never really a problem. I am used to a mbc where this occurs naturally anyway.

Greg
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Old 11-12-2003, 03:51 PM   #10
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Thanks
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Old 11-12-2003, 03:53 PM   #11
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turbo, my car, as it spools under WOT hits a point in 5th gear at about 6000 rps where the whole car shuts off, then comes back on, like some one pulled the plug on it, then the check engine light etc. it is super annoying.

MAtt
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Old 11-12-2003, 04:03 PM   #12
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Okay, thanks. I would think this problem is a boost controller problem rather than a wg size problem. I would think changing the restrictor size might be a cheap easy fix. You could make an adjustable one with a $1 fish valve.

At what boost level is it hitting boost cut?

Greg
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Old 11-12-2003, 04:08 PM   #13
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ill bet its at 17.5 psi when you get the cut.
$2$
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Old 11-12-2003, 04:48 PM   #14
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I have no guage, I have no idea what psi, the cut is
thanks guys.
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Old 11-12-2003, 05:12 PM   #15
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Man, I did not know they sold any sti's without a guage. My bad.

I recommend getting one. There is probably nothing more important than knowing what boost a turbo car is running at any point in time. The sti gauge is expensive but fits nice and look good. I used a vdo gauge with good luck on my wrx. I attached it directly to the steering column.

Good luck,

Greg
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Old 11-12-2003, 06:20 PM   #16
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Quote:
Originally posted by TurboRex
Okay, thanks. I would think this problem is a boost controller problem rather than a wg size problem. I would think changing the restrictor size might be a cheap easy fix. You could make an adjustable one with a $1 fish valve.

At what boost level is it hitting boost cut?

Greg
I wish it were that simple, but on the other side of the pond, they've taken to porting the wastegate area to smooth flow and lower resistance goint to the mouth of the wastegate. Some claim that an ECU reflash can help while other claim nothing short of porting works. Austin was seeing the same kinds of boost creep issues with his vf34 turbo on a highly modified WRX running aftermarket engine management. His "fix" was porting, though I'm not sure he ever really got rid of the boost creep. Exhaust gas was still going through the turbine despite the WG at full open, making the boost pressure creep higher and higher in the upper rev ranges.
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Old 11-12-2003, 06:50 PM   #17
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Default Re: will vf22 solve boost creep? HELPPPP

Quote:
Originally posted by pierceman
ok this is getting silly, creep, every time I drive. I'm catless, hks dp, 3" all out. I have read about the jimmy rig solution and don't like it. I know there is no utec or reflash out yet, and I don't want to prt the wastegate, but this has to stop. Do I go back to stock DP till the ecu is upgraded? Or will a vf22 solve all my issues????? Help me please, I'm still a NEWB. But did not like the search results.....

Thanks
MAtt
The only way to truely solve the problem is to port the wastegate, period. The hole needs to be enlarged and the edge of the 90 degree turn to the hole needs to be rounded to about a 1/4" radius. Buy a VF22 for cheap and port it or have it ported, then swap it in. If you've already installed a turboback, pulling the turbo itself is a peice of cake.

Kevin
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Old 11-13-2003, 10:01 AM   #18
TurboRex
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The only drawback to porting the wg is that you may be hindering the hp potential of the turbo when you actually want to run more boost. By redesigning the turbo where waste gases are encouraged to go out of the wg, you will lessen your ability to hold boost redline. That is what forced performance has instructed me.

Greg
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Old 11-13-2003, 10:39 AM   #19
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Quote:
Originally posted by TurboRex
The only drawback to porting the wg is that you may be hindering the hp potential of the turbo when you actually want to run more boost. By redesigning the turbo where waste gases are encouraged to go out of the wg, you will lessen your ability to hold boost redline. That is what forced performance has instructed me.

Greg
True, but I think that is more of a "crutch" that lets you force more exhaust gas through a housing that is a little too small. My XS500 with the huge AVO hot side housing has a very nicely rounded/ported wastegate hole - and it has proven to not have problems holding boost.

Kevin
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Old 11-13-2003, 12:42 PM   #20
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Where is everybody getting VF22s for $600?
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Old 11-13-2003, 01:46 PM   #21
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Quote:
Originally posted by wgknestrick
Where is everybody getting VF22s for $600?
me too.
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Old 11-13-2003, 01:50 PM   #22
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also, do they make vf22's in ball bearing rather than roller bearing?
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Old 11-13-2003, 04:05 PM   #23
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Quote:
Originally posted by TurboRex
The only drawback to porting the wg is that you may be hindering the hp potential of the turbo when you actually want to run more boost.
Greg
Not true. When the wastegate is shut; it is shut. It doesn't matter if you have a black hole on the other side, it is all going through the turbine.
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Old 11-13-2003, 04:17 PM   #24
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It is possible to port the wg hole where more air is being directed into the wg rather than passing the wg and going through the turbine. The key here is how you port the inlet to the wg hole. Looking into the exhaust housing and the wg inlet you will see what I am talking about.

FP custom designs their turbos to run a certain level of boost. If you change the wg hole design, this can change airflow in and out of the turbo. Whether this applies to the vf39, I do not know. The point is to be careful when porting a wg hole. Be sure you are not porting inside the housing where it can change the flow dynamics of the turbo, regardless if the wg is open or not.

Greg
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Old 11-13-2003, 04:53 PM   #25
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Quote:
Originally posted by TurboRex
Be sure you are not porting inside the housing where it can change the flow dynamics of the turbo, regardless if the wg is open or not.

Greg
If you aren't porting inside the housing, what good are you doing? Are you saying to just enlarge the wastegate hole and that's it? Isn't the point to get more air to flow through the wastegate to prevent boost creep? You have to change the flow characteristics somewhat to do this.
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