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Old 06-26-2007, 01:45 PM   #276
wrxfactor
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Quote:
Originally Posted by gatewrxing View Post
Yeah I guess it is.


How far off normal boost levels should make you concerned.
I would expect that it was protuned anywhere from the 14psi to 20psi range. Just give your tuner a call and find out what it's mapped for.
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Old 06-27-2007, 10:50 PM   #277
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Quote:
Originally Posted by Jeremy05sti View Post
That is the dumbest thing I have ever heard......Your still not changing the fact the BOOST CREEP is a mechanical issue reguardless of what you do.....
The dumbest thing I've ever heard would be somebody automatically assuming they have boost creep before eliminating other possibilities such as incorrect wastegate duty cycle mapping, incorrect orifice size on the boost control lines, stuck/siezed wastegate, etc etc.

Just because you're overboosting does not mean you have reached the physical limit of boost creep.
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Old 06-28-2007, 12:40 PM   #278
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Quote:
Originally Posted by nhluhr View Post
The dumbest thing I've ever heard would be somebody automatically assuming they have boost creep before eliminating other possibilities such as incorrect wastegate duty cycle mapping, incorrect orifice size on the boost control lines, stuck/siezed wastegate, etc etc.

Just because you're overboosting does not mean you have reached the physical limit of boost creep.


+1 for that.....
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Old 07-17-2007, 09:45 PM   #279
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Question creep question

I am going to post this here, because it has to do kind of with boost creep(Sorry if it does not belong here). So i know boost creep = bad and read all about it. I have a wrx not an sti (2007) I was going to just get a cat back to avoid boost creep all together. So i am skimming daddysscp website and i came across the MadDad(TM) Metal V2 two-piece Downpipe, I have seen this b4 nothing new but reading a lil bit more i read "The MadDad(TM) Metal V2 is the only hi-flow catted downpipe with a catless wastegate design, offering the fastest boost control response to eliminate boost creep." My big question is is that true? if i get this down pipe i will not have boost creep at all?
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Old 07-18-2007, 07:20 AM   #280
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Quote:
Originally Posted by nhluhr View Post
The dumbest thing I've ever heard would be somebody automatically assuming they have boost creep before eliminating other possibilities such as incorrect wastegate duty cycle mapping, incorrect orifice size on the boost control lines, stuck/siezed wastegate, etc etc.

Just because you're overboosting does not mean you have reached the physical limit of boost creep.
+1111111

Everyone needs to read this!!! Stop using the term boost creep...it is confusing the crap out of sooooo many people.
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Old 07-18-2007, 10:42 AM   #281
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I had mine tuned and then re-tuned several times. I couldn't keep boost under 20psi when I accelerated. Yesterday I had my wastegate ported and now it stays at 17psi and the car feels like a beast. I didn't check incorrect orifice size on the boost control lines, stuck/siezed wastegate, etc etc., but I do know that porting the wg fixed my problem.

2.5liter hybrid with td05-16g
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Old 07-19-2007, 08:29 PM   #282
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If I'm running an axleback and no other mods, would boost creep be an issue?
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Old 07-19-2007, 10:34 PM   #283
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Mate Please read this whole forum.....the answer is here.....Also read nhluhr above post.....

Originally Posted by nhluhr
The dumbest thing I've ever heard would be somebody automatically assuming they have boost creep before eliminating other possibilities such as incorrect wastegate duty cycle mapping, incorrect orifice size on the boost control lines, stuck/siezed wastegate, etc etc.

Just because you're overboosting does not mean you have reached the physical limit of boost creep.
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Old 07-20-2007, 07:59 AM   #284
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Quote:
Originally Posted by cireturbo View Post
If I'm running an axleback and no other mods, would boost creep be an issue?
Here is a good example....dude....please do some research and stop using the term boost creep. To answer your question, no you won't have any issues.
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Old 09-19-2007, 01:57 PM   #285
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Just so I understand boost creep occurs at high RPM's and if your tune is pusing ~20psi between 3-4kRPM (stage 2) it's just a boost spike?

Last edited by Kelvinz; 09-19-2007 at 02:17 PM.
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Old 09-19-2007, 02:27 PM   #286
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Quote:
Originally Posted by Kelvinz View Post
Just so I understand boost creep occurs at high RPM's and if your tune is pusing ~20psi between 3-4kRPM (stage 2) it's just a boost spike?
Boost creep occurs ANY time the wastegate cannot bypass enough exhaust gas.
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Old 09-19-2007, 02:36 PM   #287
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Quote:
Originally Posted by wrxfactor View Post
Boost creep occurs ANY time the wastegate cannot bypass enough exhaust gas.
Yes I think everyone understands that

What I am asking is how do you tell if you are creeping or spiking if your tuner has raised the fuel cut on the ECU?
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Old 09-19-2007, 05:23 PM   #288
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Quote:
Originally Posted by Kelvinz View Post
Yes I think everyone understands that

What I am asking is how do you tell if you are creeping or spiking if your tuner has raised the fuel cut on the ECU?
Get a boost gauge and compare the readings with target boost level.
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Old 09-19-2007, 06:11 PM   #289
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thanks man this sucks if only i knew what i was going to get into when i put this dam tbe on my sti oh well see if i can fix it
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Old 09-20-2007, 03:53 PM   #290
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Quote:
Originally Posted by Kelvinz View Post
Yes I think everyone understands that

What I am asking is how do you tell if you are creeping or spiking if your tuner has raised the fuel cut on the ECU?
You should know your target boost, and compare it with what you're hitting. You can log it or get a boost gauge, or do both.
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Old 09-20-2007, 04:19 PM   #291
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And hopefully your tuner hasn't set the fuel cut so damn high that it is useless...
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Old 09-20-2007, 04:59 PM   #292
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Quote:
Originally Posted by Freon View Post
And hopefully your tuner hasn't set the fuel cut so damn high that it is useless...
The tuner did do that I believe he set cut at 25psi....

Which is why I am concerned.

And yes I have a boost gauge
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Old 09-23-2007, 02:32 AM   #293
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Thanks For All The Info. All This Was A Big Help, Especially Being A Newbie. I Just Got My Sti And Obviously I Dont Want To Have Any Problems With It. This Definitely Helped Me Make A More Wise Choice Getting A Tbe Or Cbe. Thanks Guys, Keep Up The Good Info.

Chris D.
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Old 10-01-2007, 06:40 PM   #294
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I read most of the thread and it seemed mostly to pertain to STi's.
I have a 07 wrx with a turbo xs TBE that i bought and installed without knowing i needed to do anything else (im a newbie). anyways, ive been experiencing the stutter refered to in the first post and i just feel like im breaking my car. Ive been told getting the cobb stage 2 AP with eliminate this problem, but i dont have the 700 dollars right now since im in college.

besides getting the AP, is there any short term solution like reinstalling my stock axel back?

ive only had the TBE on for about 1000 miles, but could someone shine light on just how much damage i am doing to my car by keeping it on till christmas time?

Thanks in advance, i know i probably sound retarded but this is my first turbo car and im not all that mechanically inclined to begin with.
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Old 10-01-2007, 08:38 PM   #295
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If you hae a TBE without engine management, you're most certainly hitting fuel cut, as it's like 13 PSI on the stock map.

You need some engine management. Period.
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Old 10-02-2007, 12:25 PM   #296
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Quote:
Originally Posted by mcvizzle View Post
I read most of the thread and it seemed mostly to pertain to STi's.
I have a 07 wrx with a turbo xs TBE that i bought and installed without knowing i needed to do anything else (im a newbie). anyways, ive been experiencing the stutter refered to in the first post and i just feel like im breaking my car. Ive been told getting the cobb stage 2 AP with eliminate this problem, but i dont have the 700 dollars right now since im in college.

besides getting the AP, is there any short term solution like reinstalling my stock axel back?

ive only had the TBE on for about 1000 miles, but could someone shine light on just how much damage i am doing to my car by keeping it on till christmas time?

Thanks in advance, i know i probably sound retarded but this is my first turbo car and im not all that mechanically inclined to begin with.

very simple mate you if have the read this thread then please understand this......either wrx of sti......the problem still is there.....it all depends on the car and the mod.....you may or may not have problems.....The only way to make sure would be to get em and talk to a tuner.
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Old 12-23-2007, 09:27 PM   #297
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Quote:
Originally Posted by wgknestrick View Post
With the countless threads about boost creep problems with turbobacks on the 2.5l STI, I think this thread should be helpful as a quick summary to those planning on moddifying their STI.

Q) What is boost creep?
A) Boost creep occurs when the wastegate is physically unable to bypass enough exhaust around the turbine on the turbo.

Q) Is boost creep harmful?
A) Yes, boost creep is one of the worst problems you can have with a turbo engine. Boost creep means that there is NO way for the boost pressure to be controlled. Boost pressures in excess of 20psi!!! have been recorded on STIs with TBE before the ECU cuts fuel.

Q) What causes boost creep?
A) Installing a turbo back exhaust whether aftermarket catted or not will in almost all cases cause boost creep to a certain extent.

Q) Are there any other options to prevent boost creep besides porting the wastegate?
A) Yes, Installation of an exhaust that either keeps the stock OEM muffler or one of the stock cats should not cause boost creep.

Q) How do I know if I have boost creep?
A) If you have a full TBE, then you probably have it. A boost gauge will tell you what pressure you are at as well. Fuel cut occurs when the ECU senses boost in excess of 17.5psi for 2-3s. Fuel cut in my experience is a very violent "stutter" from the engine that resembles extreme knock, followed by CEL.

Q) What is the overboost CEL?
A) (P0244) Wastegate malfunction

Q) Is there anything else I can do besides porting the wastegate to prevent the creeping....MBC, EBC, engine management etc?
A) This problem is isolated to the wastegate only. The wastegate is a mechanical system. There are no current workarounds or "fixes" besides this. The 2.5l just flows too much exhaust through the turbo once a turbo back has been added for the wastegate to control boost. If you think of it as a hierarchy, then it should make sense.

level 1) wastegate controls boost pressure
level 2) boost solenoid controls wastegate
level 3) MBC/EBC/ECU controls boost solenoid

Using this logic, if the problem resides on the 1st level, no matter what you do on top of it, you will still have the problem. Whatever (MBC, EBC, UTEC, ECUTEK) is controlling the wastegate CANNOT prevent boost creep if the WASTEGATE is UNABLE TO FLOW ENOUGH EXHAUST to prevent boost creep. A fuel cut defender will not eliminate the boost creep problem, but it will stop the fuel cut. Your boost will still creep up to 20psi, but the ECU won't be able to tell due to the altered signal from the FCD.

Q) My car seems to boost creep when it is cold out. Why is that?
A) Ambient temperature plays a huge role in how well your engine runs. In general, the cooler ambient temperature, the better your engine runs due to the laws of thermodynamics. The colder air causes your engine to make more HP (more work under the curve with lower temps), therefore more energetic exhaust gases, therefore your car is more prone to boost creep when it is cold out. If you live in an area that does not see colder temperatures (AZ for example) too often, then boost creep may never become a problem.

Q) I want to port my wastegate. What do I do?
A) Can you remove and install a turbo? If yes, there are a couple of options. You can send it to Deadbolt (www.deadboltspeed.com) for porting, have a local machine shop port it, or do it yourself with a "Dremmel like" tool.

Some other info on porting:
http://rx7.freeservers.com/modhb/boostcontrol.htm
http://www.fwdmopar.com/sites/dennis/wgateport.html
http://forums.nasioc.com/forums/show...hreadid=300296
http://www.allpar.com/mopar/boost-creep.html
http://members.tripod.com/alexander_grabau/id18.htm




(edited---to fix links, add links, and include CEL code)
(edited #2---to include temperature question)

I hope this is helpful to some people and please let me know if anything needs to be corrected.

Bill
i know this is an old thread but cant you get a protune to cure boost creep
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Old 12-23-2007, 10:17 PM   #298
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Originally Posted by wsirianni View Post
i know this is an old thread but cant you get a protune to cure boost creep

you bumped it ...but did you read it ???
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Old 02-23-2008, 10:39 AM   #299
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Does someone have step by step direction for this? What tools were used? My friend and I might attempt this today as I have a divorced wastegate DP going on.
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Old 03-30-2008, 06:27 PM   #300
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so he is saying that...if I throw on a DP...I won't get boost creep because i still have my stock catback???
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