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Old 05-21-2012, 11:39 AM   #376
0wrx8
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Is boost creep still something your need to worry about in an 08wrx with no engine mods except for an exaughst (down pipe included) and intake?

Or is this really only a problem for ppl who do real engine work and blow the doors off more modest modifiers such as myself?
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Old 05-21-2012, 11:57 AM   #377
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Quote:
Originally Posted by 0wrx8
Is boost creep still something your need to worry about in an 08wrx with no engine mods except for an exaughst (down pipe included) and intake?

Or is this really only a problem for ppl who do real engine work and blow the doors off more modest modifiers such as myself?
It is more likely to occur with a full 3" TBE in conjunction with an intake. That setup reduces a lot of restriction, so boost creep could be an issue. It also depends on the car, as each car responds differently. Weather and temperature also play a role, the colder being more likely to cause creep, when using the aforementioned combo of exhaust + intake.

I personally have an intake, catless downpipe and Nameless Performance muffler deletes, and I have 0 boost creep. I still have the stock midpipe though, so it does cause a little bit of restriction to help cut down on the possibility of boost creep.

If your catback has mufflers, boost creep shouldn't be a problem, as it's fairly rare on the newer cars. Worst case, you'll have to take off the aftermarket intake during the winter and install the stocker.
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Old 05-21-2012, 11:58 AM   #378
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08+ cars are especially prone to boost creep with an aftermarket intake and a turboback exhaust.

If you leave the stock intake on the car they are much less likely to have boost creep and if it does its usually not that severe and can be tuned out.
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Old 05-21-2012, 12:59 PM   #379
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Quote:
Originally Posted by Tripintaz
08+ cars are especially prone to boost creep with an aftermarket intake and a turboback exhaust.

If you leave the stock intake on the car they are much less likely to have boost creep and if it does its usually not that severe and can be tuned out.
Not true at all. The earlier models before 08 were much more prone to experiencing boost creep. Also, tuning has absolutely NOTHING to do with boost creep. Boost creep is a mechanical issue, period, and can only be resolved through an EWG setup as porting the wastegate is not always 100% successful.
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Old 05-21-2012, 03:30 PM   #380
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Quote:
Originally Posted by J_Maher_WRX View Post
Not true at all. The earlier models before 08 were much more prone to experiencing boost creep. Also, tuning has absolutely NOTHING to do with boost creep. Boost creep is a mechanical issue, period, and can only be resolved through an EWG setup as porting the wastegate is not always 100% successful.
It's absolutely true. Boost Creep being mechanical and not tunable only applies to a specific setup on 08+ cars. With stock TMIC, aftermarket intake and turbo back exhaust boost creep is not solvable via tune a majority of the time. But this does not mean that all set ups that experience boost creep are unsolvable via tune and/or other paths.

Boost creep is a direct relation to waste gate duty. If you are boost creeping and your wastegate DC is 40% then you CAN tune it out. It is common for an 08+ WRX with full turboback exhaust and STOCK intake to experience a small amount of creep. However, with the proper tune it can be eliminated since the WGDC's are still in a high enough range that it can be adjusted.

Move to an aftermarket intake AND full turboback exhaust and now you are starting to get the WGDC's so low that even at 0% DC the car is over boosting. This comes to the point where it cannot be tuned out.

What year WRX do you have? Have you tuned any 08+ WRX/STI's yourself and speak from experience? EWG is an option, but not the only path to solving boost creep on the GR's.
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Old 05-21-2012, 05:09 PM   #381
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I know this thread started off as an STI thread but I am assuming this applies to all turbo cars. I have an 07 wrx. AP. cobb down pipe and a stromung cbe. I still have not put them on yet. Should I be worried? Should I consider porting the WG before even putting them on and getting it tuned? I am runing stock everything else including intake. Is an external waste gate the more ideal way to go rather than porting the stock one? Not sure I understand what an EWG set up is still reading into it.
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Old 05-24-2012, 12:30 AM   #382
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Quote:
Originally Posted by Tripintaz View Post
............ If you are boost creeping and your wastegate DC is 40% then you CAN tune it out. ........
If your WGDC is only 40%, then by definition, you're not 'boost creeping'.

Boost creep is when the tuning is at 100% and your boost is still 'creeping' higher, due to mechanical flow limitations at the wastegate.
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Old 05-24-2012, 10:19 AM   #383
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Originally Posted by StealthTL View Post
If your WGDC is only 40%, then by definition, you're not 'boost creeping'.

Boost creep is when the tuning is at 100% and your boost is still 'creeping' higher, due to mechanical flow limitations at the wastegate.

Who made this definition? If the ECU cannot remove enough WGDC to keep the boost from climbing but the WGDC is still at 40% would you just call this overboosting then instead of boost creep?

So according to semantics, if you can tune it out its overboosting, but if you cant its boost creep? Semantics aside, everything else I have said is true and accurate.
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Old 06-05-2012, 12:31 AM   #384
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I have the o2 sensor code being thrown on my 05 wrx with tbe and results in a cel, will my Cobb ap v2 stage 2 tune take care of the problem?
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Old 06-05-2012, 12:30 PM   #385
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Quote:
Originally Posted by C-bird6969 View Post
I have the o2 sensor code being thrown on my 05 wrx with tbe and results in a cel, will my Cobb ap v2 stage 2 tune take care of the problem?
You are in the wrong area, should be posted in the AccessPort area.

From one of the map notes on the Cobb map web page
CEL Codes Defeated [WHEN USING AS BASE MAP]:
P0037 - Rear O2 Sensor Heater Control Circuit Low
P0038 - Rear O2 Sensor Heater control Circuit High
P0137 - Rear O2 Sensor Circuit Low Voltage
P0138 - Rear O2 Sensor Circuit High Voltage
P0139 - Rear O2 Sensor Circuit Slow Response
P0420 - Catalyst System Efficiency Below Threshold
P0545 - Exhaust Gas Temperature Sensor Circuit Low
P0546 - Exhaust Gas Temperature Sensor Circuit High
P1301 - Misfire Detected (High Temperature Exhaust Gas)
P1312 – Exhaust Gas Temperature Sensor Malfunction
P1544 – Exhaust Gas Temperature Too High

Cobb map web page.
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Old 06-05-2012, 03:21 PM   #386
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Ok, I've read through a good bit of this, and just want the educated opinions I can get here.

I have an 08' WRX that shortly will have a CNT Catted DP, Possibly the Grimmspeed Ported manifold, and depending on advice, without the GS up-pipe. It will have the stock Intake, and the custom exhaust with muffler delete, w/ turndown. This if for SCCA STX Solo, and will have a Cobb pro-tune done, or one at MZM here in austin, with, per rules, boost not touched.

Boost Creep an issue ? I guess a slight amount would be welcome, as it's legal as long as it isn't changed manually by tune. From what I've read, since the boost will be low, and I'll be keeping at least one cat, dangerous creep shouldn't be an issue, but I'm wondering how much I may still get ?

This is what it looks like a typical STX tune is going to look like for the 08' (Red)

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Old 06-05-2012, 04:31 PM   #387
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Quote:
Originally Posted by MurphysLaww View Post
Ok, I've read through a good bit of this, and just want the educated opinions I can get here.

I have an 08' WRX that shortly will have a CNT Catted DP, Possibly the Grimmspeed Ported manifold, and depending on advice, without the GS up-pipe. It will have the stock Intake, and the custom exhaust with muffler delete, w/ turndown. This if for SCCA STX Solo, and will have a Cobb pro-tune done, or one at MZM here in austin, with, per rules, boost not touched.

Boost Creep an issue ? I guess a slight amount would be welcome, as it's legal as long as it isn't changed manually by tune. From what I've read, since the boost will be low, and I'll be keeping at least one cat, dangerous creep shouldn't be an issue, but I'm wondering how much I may still get ?

This is what it looks like a typical STX tune is going to look like for the 08' (Red)
I doubt you will have boost issues using the stock airbox. On a side note, why do they limit the power so much? It would be no fun to drive a car that has a castrated tune IMO.
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Old 06-06-2012, 10:13 PM   #388
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Well, it's not so castrated. One of Clubs STU guys makes more hp from his STU map than a straight Stage 2.

It's just the rules for Street Touring. Each class is one step from stock and ST is just one step from Stock. You can begin messing with boost in Street Prepared. I believe they are trying to have classes for different levels of budget.

It's a good idea, as I don't think I'd enjoy running the 08' on stock spring rates, but don't have the $$$ to do a whole built engine, etc. It's also my daily, so I don't want to have to do too much work to get it back livable after an event. ST class is a good fit for me this year, until I can afford a tow vehicle.
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Old 06-07-2012, 09:29 AM   #389
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Ah, I failed to notice that was a graph from an 08 WRX with the td04. That explains the fall off in boost and HP in the upper RPM's. I suppose on the track you don't spend much time in that area or the RPM band anyhow.
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Old 06-18-2012, 12:30 AM   #390
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So let me get this straight. I have an 05 wrx I'm looking to install a ap, and I have a turbo xs cat less dp to install on it. So not matter what as soon as I install the dp I'm going to get boost creep? And one of the only ways to get rid of it is to port the Wastegate? any other options?
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Old 06-18-2012, 03:51 AM   #391
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Quote:
Originally Posted by sweetmf14
So let me get this straight. I have an 05 wrx I'm looking to install a ap, and I have a turbo xs cat less dp to install on it. So not matter what as soon as I install the dp I'm going to get boost creep? And one of the only ways to get rid of it is to port the Wastegate? any other options?
Your question is somewhat irrelevant here because your '05 has a 2.0 liter engine. 2.0 liter's still experience boost creep, but 2.5's are more prone to it. And NO, you will not automatically experience boost creep just because you slap a TBE on your car. It's completely circumstantial. Cars react differently to temperature, elevation, humidity, etc. Not everybody WILL have boost creep problems, even with a catless DP, I am one to say. I haven't seen a lick of boost creep since my Cobb Stage 2 conversion with a catless divorced WG DP. Then again, every car is different.
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Old 06-27-2012, 07:40 AM   #392
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I am getting boost creep with my FP black at 27psi ... I can run 26psi without issues but if I turn it up a little . I am going to have to pull my turbo and port it.

I would recommend that everytime people get a new turbo they should port the wastegate
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Old 06-27-2012, 08:48 PM   #393
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Ive been running an Injen CAI since nov '11 with no problems. Added stage one Cobb AP dec '11, no problem. Dropped in an Injen catless downpipe onto my STP exhaust and reflashed to stage 2 Cobb AP about 2 weeks ago, PROBLEM! LoL When I am cruisin around 70Mph the check engine light comes on and the SI-drive "S" and cruise control light start blinking... Cobb code reader says P0137 O2 sensor circuit low voltage (bank 1 sensor 2). I went back and checked all of the hoses and connections everything looks good. Im wondering if I need a custom tune? I want to try and diag problem before I take it to the dealership.
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Old 06-27-2012, 09:30 PM   #394
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Quote:
Originally Posted by dmzday2012
Ive been running an Injen CAI since nov '11 with no problems. Added stage one Cobb AP dec '11, no problem. Dropped in an Injen catless downpipe onto my STP exhaust and reflashed to stage 2 Cobb AP about 2 weeks ago, PROBLEM! LoL When I am cruisin around 70Mph the check engine light comes on and the SI-drive "S" and cruise control light start blinking... Cobb code reader says P0137 O2 sensor circuit low voltage (bank 1 sensor 2). I went back and checked all of the hoses and connections everything looks good. Im wondering if I need a custom tune? I want to try and diag problem before I take it to the dealership.
First of all, Cobb doesn't have a map available tuned for the Injen intake. So yes, in order for your car to run properly, you will need a custom tune.

Second, the code you are getting probably has to do with the fact that you are running a catless downpipe. You can fix this with the accessport.
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Old 06-27-2012, 10:04 PM   #395
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Quote:
Originally Posted by juanmedina View Post
I am getting boost creep with my FP black at 27psi ... I can run 26psi without issues but if I turn it up a little . I am going to have to pull my turbo and port it.

I would recommend that everytime people get a new turbo they should port the wastegate

what spring is in the wg actuator???
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Old 06-27-2012, 10:07 PM   #396
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Quote:
Originally Posted by dmzday2012 View Post
Ive been running an Injen CAI since nov '11 with no problems. Added stage one Cobb AP dec '11, no problem. Dropped in an Injen catless downpipe onto my STP exhaust and reflashed to stage 2 Cobb AP about 2 weeks ago, PROBLEM! LoL When I am cruisin around 70Mph the check engine light comes on and the SI-drive "S" and cruise control light start blinking... Cobb code reader says P0137 O2 sensor circuit low voltage (bank 1 sensor 2). I went back and checked all of the hoses and connections everything looks good. Im wondering if I need a custom tune? I want to try and diag problem before I take it to the dealership.
this has nothing to do with boost creep and EVERYTHING to do with using parts that dont fit the tune

the 'cobb code reader' isnt a code reader

you will blow it up soon i think
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Old 06-28-2012, 04:02 AM   #397
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Im new to the forum and was unable to create a new post didn't know a better way of getting my question out there. And my AP is what showed me the code P0137 in the trouble shooting function. I wasnt calling it a code reader just describing the tool I used and what it displayed.
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Old 06-28-2012, 04:18 AM   #398
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Quote:
Originally Posted by dmzday2012 View Post
Ive been running an Injen CAI since nov '11 with no problems. Added stage one Cobb AP dec '11, no problem. Dropped in an Injen catless downpipe onto my STP exhaust and reflashed to stage 2 Cobb AP about 2 weeks ago, PROBLEM! LoL When I am cruisin around 70Mph the check engine light comes on and the SI-drive "S" and cruise control light start blinking... Cobb code reader says P0137 O2 sensor circuit low voltage (bank 1 sensor 2). I went back and checked all of the hoses and connections everything looks good. Im wondering if I need a custom tune? I want to try and diag problem before I take it to the dealership.
Yes, you absolutely need a custom tune.

The Cobb Stage 2 tune is intended for either Cobb or AEM intake (different tune for each), with Cobb catted DP (or similar). The requirements are all clearly written in the notes for the tune.

You are running an intake, and a catless downpipe, on an OTS tune not designed for either one .. of course your having issues.
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Old 06-28-2012, 04:55 AM   #399
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Quote:
Originally Posted by GrumpyPitbull View Post
Yes, you absolutely need a custom tune.

The Cobb Stage 2 tune is intended for either Cobb or AEM intake (different tune for each), with Cobb catted DP (or similar). The requirements are all clearly written in the notes for the tune.

You are running an intake, and a catless downpipe, on an OTS tune not designed for either one .. of course your having issues.

Downloading Cobb's free tuning program tomorrow got too excited with everything didnt take time to think things through. I'm hopeful this will solve the problem. Thanks!
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Old 07-29-2012, 03:04 AM   #400
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So I read through the entire thread and from what I understand, boost creep can not be fixed via a tune and porting the IWG doesn't necessarily fix the issue. Correct?

Also, one of the ways to handle boost creep is by utilizing an EWG. At least that's what I've read. I also read that a 3-port boost control solenoid can do the trick (http://forums.nasioc.com/forums/show....php?t=2334925). True?

Finally, is boost creep only an issue in higher gears (5th-6th) at rpm's above 5k? Or is the gear irrelevant?
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