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Discussion Starter · #1 · (Edited)
I'm running a 3 inch TXS turbo back, no cat, RFL Muffler. I also have a K&N Typhoon.

I did a little mapping tonight and got some disturbing boost numbers. Although everything seems to settle down to reasonable numbers after a bit, but towards the end of the log it looks as if I'm starting to creep. In any case I'm very concerned.

First off I'm going to switch to the stage 2 LWG Map, and order a CAT for my turbo back. Any thoughts as to what else I can do to prevent the spikes into 20+ psi.

Does anyone think I'm over reacting? Would just the map or the Cat only likely solve my issue?

All thoughts would be appreciated.
 

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The Hoff Fan Club, member #001
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the intake doesn't cause boost creep. Getting a custom tune would be very wise, sometimes it's an EM problem (so a tune can fix it) and sometimes it's a hardware problem (getting tuned would still be a very good idea, but the only way to really fix it would be porting or an external wastegate).
 

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I agree with the Hoffman... But I also think that having a highflow cat with LWG Map should solve the issue. The HF cat will provide some of the restriction that PKSkull77 had when he was running catless w/ stock axleback.
 

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Discussion Starter · #6 ·
Pro tune is definitely an option, just not the first step I’m going to take. I think running the LWG duty map will clear up the boost spikes, as it appears the waste gate is capable of releasing the pressure; it’s just not opening early enough.

Hopefully the cat will clear up the boost creep looking data towards the end of the run.

One thing I did notice, is that the waste gate is only open into the low 40’s to upper 30’s towards the end of the run (corresponding to the time when the boost started to rise). Is there any particular reason why the map wouldn’t keep the waste gate open to a higher level in order to prevent boost creep (notice that my levels are hitting target when it is open just a bit more)? Or, is what I’m looking at an effect of creep rather than the cause?
 

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Discussion Starter · #7 ·
Does anyone out there have a Log of their car when it is suffering from "boost creep"??? I've run a couple of searhes and I can't find a thing.
 

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its probably due to you running a catless system. Get a cat / and or protune and that might solve it.

idk if porting the wastegate would help with spike, i know it helps with creep most of the time.
 

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I think it's a bunch of bull if people say you can run a Cobb intake but no other SRI. The flow is going to be same.
[/quote]

The problem lies in the air flow over the MAF sensor. When you change the dimensions of the maf housing(as in a CAI), the air speed inside the cai will be different from the stock air box, causing obscure maf voltage.
 

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flatthump said:
The problem lies in the air flow over the MAF sensor. When you change the dimensions of the maf housing(as in a CAI), the air speed inside the cai will be different from the stock air box, causing obscure maf voltage.
That is precisely what Nhluhr (Nick) has proven to be incorrect, at least with the K&N Typhoon. He has done extensive datalogging and it has proven that the MAF readings are spot on with the stock intake. I can't say the same for other intakes, but I can with the Typhoon. Plus, even with a different MAF reading, this wouldn't cause the car to overboost. The boost regulation isn't a result of the MAF, Air/Fuel ratio on the other hand is.
 

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I had an 06 STi with the Perrin catless DP, and the HKS Hi-Power CB and I was also flashed Stage 2. I had serious boost creep and was hittin way to much boost. COBB told me it was because of the catless DP. I ran their LWG map and it still didnt help, after that I ran a catted DP and problem was solved.

Nick
 

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STEye said:
That is precisely what Nhluhr (Nick) has proven to be incorrect, at least with the K&N Typhoon. He has done extensive datalogging and it has proven that the MAF readings are spot on with the stock intake. I can't say the same for other intakes, but I can with the Typhoon. Plus, even with a different MAF reading, this wouldn't cause the car to overboost. The boost regulation isn't a result of the MAF, Air/Fuel ratio on the other hand is.
Yes yes....except fo the typhoon.
 

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i dont know 20 psi is fine if it only sits up there for a little bit .. i know my buddie is running stage 2 and will hit like 21 psi and it will go back down to like 18 or so . I would not be worried about it get a protune and u will be set
 

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If I were you I would call try the LWG map and call COBB, if that doesn't work and you still throw a check engine light I would swap for a catted DP. It only takes one time to hit to much boost and ruin something. I know a kid who pop'd his STi at 500 miles because of a similar issue and he drove it like an idiot because he really never had a break in period other than the first gas tank. To each is their own though, this is just my .2 cents!

Nick
 

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I dont think its anything major. ONCE in a blue moon on a cold night I spike 20-21 in 4th gear. My car runs great. Your car should be pulling hard spiking 20+, so long as you dont hit fuel cut. I don't.

Edit: I have no cats as well.
 

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Discussion Starter · #18 ·
Thanks for the advice guys. Like I said the cat is on the way, and should be installed no later than this weekend. In the mean time I'm driving my beater to and from work, so no worries about popping the motor.

I'm not going to flash it till I get the CAT on. I want to see if the CAT resolves the issue, rather than switching maps only to find out that I'm not hitting target boost becuase the system is now to restrictive.

However, something tells me I'll be going to stage 2 LWGD in any case. I had to LWGD stage 1, so I don't see why stage two should be any different.
 

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I think you should flash and datalog first, then if for some reason it solves your problem, you don't have to put on the cat. At the very least, I would try the LWG realtime map on top of your normal stage 2 map. That way you don't have to "reflash" your ECU to see if there is benefit from LWG. I would also do more datalogging each step of the way, even with the current setup you have now. Post the logs! I want to see what helps and what doesn't..
 

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STEye said:
I think you should flash and datalog first, then if for some reason it solves your problem, you don't have to put on the cat. At the very least, I would try the LWG realtime map on top of your normal stage 2 map. That way you don't have to "reflash" your ECU to see if there is benefit from LWG. I would also do more datalogging each step of the way, even with the current setup you have now. Post the logs! I want to see what helps and what doesn't..
X2 I was going to say the same thing.
 
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