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Old 02-02-2013, 04:42 PM   #426
jaboyd
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Boost creep is uncontrolable and varies with temp....not a good thing!
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Old 02-05-2013, 01:03 PM   #427
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Hey I guys, new on the forums and just bought an 06 WRX this past weekend. I've been researching and reading up on all the FAQs but I have a question regarding WGs. I understand that creep will become an issue once too much exhaust flow passes through the stock WG for it to compensate the pressure difference in the turbo.
So my questions are, would a WG like Tial work better than just porting the stock WG? If so, how do you know what size to get? How do you go about installing an aftermarket EWG? Am I even thinking of this the right way?
If there's any thread about this already just point me to the right direction. Thanks

Planned mods:
Cobb sf intake
Turboxs catted tbe
Eqtuning crosspipe
Turboxs up pipe???
Cobb accessport stage 2
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Old 02-05-2013, 01:13 PM   #428
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Default boost creep

Basically I ran the same mods on my 05 STI except for the Cobb SF intake. I didn't go the CIA route bc when coupled with the rest of your mods you'll have a potential for creep. By remaining with the oem air box you'll eliminate the need for the EWG or other WG changes. The stock box will handle 350whp and wo/any issues and will give very good overall performance. I'd suggest saving your money on the SF and WG controls and spend it on a pro-tune.
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Old 02-06-2013, 10:15 AM   #429
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Not sure if it's been asked yet but instead of porting the stock wastegates would it be better to install a larger diameter aftermarket wastegates to make up for the flow resistance. ? I have a stock 09 wrx. Planning on going stage 2+ right away and would love to avoid the creep.

Edited. Didn't see the post two above me asking pretty much thus same thing lol

Last edited by mccadney; 02-06-2013 at 10:23 AM.
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Old 02-06-2013, 01:57 PM   #430
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Quote:
Originally Posted by mccadney View Post
Not sure if it's been asked yet but instead of porting the stock wastegates would it be better to install a larger diameter aftermarket wastegates to make up for the flow resistance. ? I have a stock 09 wrx. Planning on going stage 2+ right away and would love to avoid the creep.

Edited. Didn't see the post two above me asking pretty much thus same thing lol
"Better" is a matter of opinion; and how big your wallet is.

EWG: no chance of boost creep but very expensive and requires a custom tune / ATR to control the EWG.

IWG: chance of boost creep (depends on many factors though) but is MUCH cheaper and can use an OTS map.
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Old 02-06-2013, 02:12 PM   #431
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Default creep

At this pt is this simply your concern that you might get creep? If so, then stick w/stk airbox and its unlikely you'll have an issue. If your desire is for over 340hp (you can get to 330 - 340hp with stk airbox, stage II and changes to exhaust. If that is insufficient then I'd probably invest in a drop in turbo upgrade (passes more air) and your mods.....doubt you'd need an EWG.

The point is as you approach 350hp you'll need to support that power w/injectors, fuel pump and EBCS upgrades anyway, so the next size up turbo will give you the power and not be at its max.
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Old 02-06-2013, 03:30 PM   #432
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Feel free to pm me about EWG setups, anything from sizing to boost controller setups. I researched the crap outta these things before buying mine and I love it
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Old 02-07-2013, 12:17 PM   #433
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Quote:
Originally Posted by jebjkey View Post

"Better" is a matter of opinion; and how big your wallet is.

EWG: no chance of boost creep but very expensive and requires a custom tune / ATR to control the EWG.

IWG: chance of boost creep (depends on many factors though) but is MUCH cheaper and can use an OTS map.
Plan on using Cobb ap for tuning. AEM CAI, COBB downpipe, SPT catback. Pockets ain't too deep but I'm about to drop 2k on stage 2+ but if that ends up giving me the creep I may need to get an ewg also. More research to do. Would the AP tune work for an ewg do u know? Or would I need a protune
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Old 02-07-2013, 02:14 PM   #434
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hey guys, I have an 05 STi with only an AMR catback exhaust on an otherwise stock powertrain/ECU. I threw the wastegate performance CEL and hit the fuel cut yesterday on the highway while it was ~34 degrees out @ ~5500 RPM in 5th. I'm curious if a dyno-tune would fix this problem by generating a fuel/timing map for the higher boost range as I doubt that I'm reaching over 20 PSI with just a catback.

Any thoughts?
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Old 02-07-2013, 02:25 PM   #435
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Quote:
Originally Posted by mccadney View Post
Plan on using Cobb ap for tuning. AEM CAI, COBB downpipe, SPT catback. Pockets ain't too deep but I'm about to drop 2k on stage 2+ but if that ends up giving me the creep I may need to get an ewg also. More research to do. Would the AP tune work for an ewg do u know? Or would I need a protune
A free flowing exhaust with the stock turbo usually results in boost creep and an EWG is an excellent way to get rid of it. No OTS maps from COBB will work with an EWG and on top of that, you may want to upgrade your boost controller to either an EBCS or MBC. You will need to get an e-tune or protune if you go this route. PM me if you want to discuss EWGs further

Quote:
Originally Posted by gamma1232 View Post
hey guys, I have an 05 STi with only an AMR catback exhaust on an otherwise stock powertrain/ECU. I threw the wastegate performance CEL and hit the fuel cut yesterday on the highway while it was ~34 degrees out @ ~5500 RPM in 5th. I'm curious if a dyno-tune would fix this problem by generating a fuel/timing map for the higher boost range as I doubt that I'm reaching over 20 PSI with just a catback.

Any thoughts?
If the only mod you have is a catback (no ECU flash or extra bolt-ons), then you are seriously overboosting. Make sure all the boost hoses are connected to your turbo, IWG, turbo inlet, and boost controller. PM me if you need any clarifcation on what I am talking about.
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Old 02-07-2013, 02:58 PM   #436
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I should clarify that I dont think I actually hit 20 PSI....just that with the slightly less restrictive exhaust that I'm over-boost to ~16ish PSI which would put me out of range on the stock map and causing the ECU to think the WG isn't operating properly; hitting the fuel cut. I don't want to remove the exhaust and I think the stock engine and turbo and good to 20 PSI (correct me if I'm wrong), which is why I asked if a pro-tune could potentially solve this by generating a fuel map that has timing and boost target values above 15psi
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Old 02-23-2013, 07:02 PM   #437
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will simply changing the turbo to a direct bolt on fix boost creep?
for example a godspeed td05.
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Old 02-24-2013, 10:37 AM   #438
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Short answer: it could.
Longer answer: it really depends on too many factors to accurately predict.
Unfortunate answer: EWG is the only guaranteed way to eliminate boost creep.

Look for other people who have the turbo you are looking at and see what they have to say.

Or, talk to your tuner and see what they recommend.

The real unfortunate part, there is A LOT of misinformation concerning boost creep out there. Many people claim to have a problem with boost creep when they actually just have a tuning problem. You do not know if you have boost creep or a tuning problem unless you have appropriate data logs or do a test.

I know I have a problem with boost creep because I have tested for it and I also have numerous data logs that show the ECU trying to control boost by adjusting WDC to 0. I also know my stock air box is required to keep boost creep under control. Look for my thread on boost creep and you will see what I am talking about.
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Old 08-20-2013, 08:15 PM   #439
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Just to clarify, is this also an issue on 2.5l WRX's or is this primarily an STI issue?
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Old 08-20-2013, 08:21 PM   #440
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Quote:
Originally Posted by Skoobz View Post
Just to clarify, is this also an issue on 2.5l WRX's or is this primarily an STI issue?
Has absolutely nothing to do with model... Has to do with airflow. Catless, no mufflers, intake, highly likely to experience boost creep in colder temps.
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Old 08-20-2013, 08:23 PM   #441
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Quote:
Originally Posted by J_Maher_WRX View Post

Has absolutely nothing to do with model... Has to do with airflow. Catless, no mufflers, intake, highly likely to experience boost creep in colder temps.
Thanks! I just didnt know if the different turbo/wastegate on the STI is what was causing the issues.
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Old 10-08-2013, 09:59 PM   #442
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I read through the thread as best I could. Will creep occur if I do a down pipe catless to the stock cat then through a nameless exhaust ?
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Old 10-08-2013, 11:12 PM   #443
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I read through the thread as best I could. Will creep occur if I do a down pipe catless to the stock cat then through a nameless exhaust ?
Bah what? Do you actually know where the stock cats are located? You are you going to Fab your own system?
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Old 10-09-2013, 07:21 AM   #444
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Originally Posted by bagelswrx View Post
I read through the thread as best I could. Will creep occur if I do a down pipe catless to the stock cat then through a nameless exhaust ?
As stated, boost creep is all about airflow, and your wastegate's ability to handle that airflow. The more restrictions you remove, the more air you flow, and the more likely the chance of creep. None of us can really tell you with any certainty if you will creep with this or that set-up, there are too many variables such as tune, climate, etc.

As for your question, the catalytic converters on a turbo Subaru are located on the downpipe. If you replace the stock downpipe with a catless one, then you will have no catalytic converters at all. Will you get boost creep by going catless? Maybe .. see paragraph #1.
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Old 10-09-2013, 07:42 AM   #445
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Delete

Last edited by browntruck2247; 11-07-2013 at 12:41 PM.
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Old 01-02-2014, 04:05 PM   #446
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Default Great thread

First off I have that user name because I own a 1974 BMW 2002 and it is easy for me to remember....so no BMW prick guy jokes LOL....well I guess WRXnick would have been easy as well. Ok you can make fun of me then.

This has been a great thread to read. I have a stage 2 2012 WRX. SF intake, Nameless Down tube, midpipe and ABE. I went by Cobb today to ask about pro-tunes. The guy asked what I had and if I had turbo creep. I am new to turbos so had no idea what he meant. I told me to hook up my Accessport and watch my boost, do a few hard pulls and tell him what happened. On the way home I did a few 3500-redline WOT in 3rd, 4th and 5th. My boost went up to 18-20.2 range. It was 28 degrees outside which is not helping.
I reported my findings and he said it is turbo creep.

So I do some research and find this thread. Read it all. Was very informative. Now for a few questions just to make sure I am clear on it all.

The factory exhaust has restriction which causes the turbo to spool to a certain level...then the back pressure keeps it at a certain speed..which helps physically regulate boost.

When the exhaust is opened up like in a full turbo back setup..this restriction is gone, so much less back pressure to keep the turbo from spooling up past recommended max boost.

This is where I am getting a bit confused with porting the waste gate. I am not understanding how making the waste gate flow better will slow the spooling of the turbo to drop boost back to where it needs to be. Since you are making this side flow even better wouldn't it actually cause the turbo to spool even faster do to even less back pressure?

I also read that putting the stock air cleaner system back on can get rid of boost creep. I called Cobb and they confirmed this can often help to a degree.

So my take on it all is to reduce or stop turbo creep I need to either introduce some restriction back into the exhaust ( I won't be doing this) or decrease to amount of air being fed in by putting the stock intake back on.

It just seems the best way to do it and not decrease performance is to port the waste gate but I need to be able to better wrap my mind this portion of it.

After you guys bust my balls I am hoping for some better insight about the porting
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Old 01-02-2014, 04:13 PM   #447
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i wouldn't bother porting the turbo and just go with an EWG setup. look up grimmspeed/tial setups.
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Old 01-02-2014, 04:16 PM   #448
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I have. 2011 STI stage II w/catless dp Q300 TBE. I believe your assessment is basically correct. The wastegate porting I believe is used to more effectively relieve the excess pressure rather than using intake or exhaust resitriction.

I had boost creep when I had a CIA so I went back to stock box and that stopped the creep, however it also traded off max power at the upper end of the rpm range ti think exhaust restriction would act similarly). Wastegate porting should allow you to open up both intake/exhaust and more effectively address creep.

On the street using the stk intake to restrict creep worked fine.
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Old 01-02-2014, 04:30 PM   #449
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Quote:
Originally Posted by jaboyd View Post
I have. 2011 STI stage II w/catless dp Q300 TBE. I believe your assessment is basically correct. The wastegate porting I believe is used to more effectively relieve the excess pressure rather than using intake or exhaust resitriction.

I had boost creep when I had a CIA so I went back to stock box and that stopped the creep, however it also traded off max power at the upper end of the rpm range ti think exhaust restriction would act similarly). Wastegate porting should allow you to open up both intake/exhaust and more effectively address creep.

On the street using the stk intake to restrict creep worked fine.
I had read on this forum that adding a cold air intake type setup like COBB really does not improve performance anyway unless you are over 350HP. So with this thinking going back to the stock intake would not really be a performance loss at all if nothing was gained....does this sound right?

reason I ask is because on my access port it asks if I run an SF intake. So I assume it must be asking because it makes a difference somehow...
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Old 01-02-2014, 04:35 PM   #450
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Yes, CIA affects tune so you need to pick which ever one you want.
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