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Discussion Starter · #1 ·
I'm at the tuner's now...had my 20g turbo and supporting mods installed and tuned about a month ago but had severe boost creep. Decided to go EWG. Car on dyno w/ EWG and IWG held shut. Boost still wouldn't hold. Tuner decides to run both external and internal WG's together...and now it's apparently holding fine.

Can someone explain this to me while i'm waiting?! I'm under the impression that running both EWG and IWG will cause problems with regulating boost...??
 

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He's either incredibly smart or incredibly stupid..........I really don't know but I've always herd that running both can cause low boost problems.
 

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Discussion Starter · #3 ·
Forgive my 'noobiness'. Just spoke w/ tuner. I have a little bit of insight now. According to him, the EWG I put in place wasn't large enough (38mm). This is why it still wasn't holding boost properly...with that, he opened up the IWG as well to make the wastgate hole 'bigger'. Make sene?! So i'm basically maximizing the internal wastegate and whatever is 'overflowing' gets filtered by the external one.
 

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STiLL said:
Forgive my 'noobiness'. Just spoke w/ tuner. I have a little bit of insight now. According to him, the EWG I put in place wasn't large enough (38mm). This is why it still wasn't holding boost properly...with that, he opened up the IWG as well to make the wastgate hole 'bigger'. Make sene?! So i'm basically maximizing the internal wastegate and whatever is 'overflowing' gets filtered by the external one.

aa i get it! :)

can i have my cookie now?
 

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that cant be the case because i have a 38 mm turbosmart EWG and a FP red turbo and mine is fine
 

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STiLL said:
Forgive my 'noobiness'. Just spoke w/ tuner. I have a little bit of insight now. According to him, the EWG I put in place wasn't large enough (38mm). This is why it still wasn't holding boost properly...with that, he opened up the IWG as well to make the wastgate hole 'bigger'. Make sene?! So i'm basically maximizing the internal wastegate and whatever is 'overflowing' gets filtered by the external one.
thats not right. EWG's don't work in the sense that a bigger wastegate for a bigger turbo. Look at this thread and look at Eatv8's post. Stuff directly from the turbosmart website.

http://www.iwsti.com/forums/showthread.php?t=55810
 

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Discussion Starter · #10 ·
Ok. I understand that thread on the EWG, but here are the facts regarding my situation.

-w/ IWG only: Boost creep; hit about 1.5bar and then advance to about 1.7bar hold and then boost cut. This happend everytime during 5th gear pulls.

-w/ EWG only (internal gate held shut): Boost now pegging and holding, but holding at 1.8bar and not going down. We tried a restrictor pill and still nothing. Boost would not drop below 1.7bar, boost cut. This happend from 3rd gear all the way up.

-Kept using the EWG and opend the IWG: Car ran perfectly. It was holding steady boost at about 1.53bar all the way up to red line w/ very minimal taper. Boost curve was very smooth (line w/ green dots through them).

This seemed to keep the car happy and made the car run extremely well! Very smooth and very fast! It seems like the EWG isn't opening up that much either. Under WOT you can barely hear it working, but it is getting rid of the excess boost that can't escape through the IWG...

It may not make sense, but the car seems happiest like this...

Final: 343WHP and 355WTQ on pump 94OCT gas.
 

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Hmm something does sound fishy usually when you have a EWG there either is no internal one at all or it's welded shut if not you have a more likely chance of boost not holding. Perhaps the tuner is not adjusting the wastegate duty cycle? Its not like your boosting super high either so a 44mm wouldn't be needed. Do you have a manual boost controller? Stock boost solenoid can handle only up to 22 PSI i think. Something just doesn't sound right I would try to figure out the problem in case it causes future problems just my 2 cents.
 

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droopy172 said:
Hmm something does sound fishy usually when you have a EWG there either is no internal one at all or it's welded shut if not you have a more likely chance of boost not holding. Perhaps the tuner is not adjusting the wastegate duty cycle? Its not like your boosting super high either so a 44mm wouldn't be needed. Do you have a manual boost controller? Stock boost solenoid can handle only up to 22 PSI i think. Something just doesn't sound right I would try to figure out the problem in case it causes future problems just my 2 cents.
I was just going to say something like that. How was your IWG held shut? Generally it is welded. I don't know how he would have opened it without removing everything and doing some major work.

Also, what spring is in your EWG? If it won't boost below 1.8 bar maybe that is the springs it has in it.
 

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Discussion Starter · #13 ·
They used something to jam the internal wastegate shut ( didn't see them do it ). So to open it again, they just removed that piece keeping it together.

The spring issue i'm not too sure about. I'll find out a little later.

All i know is that I saw the boost curve when using both IWG and EWG and it was almost a straight line. The car runs amazing and everything seems to be working fine...

Do you think i really need to worry?! I mean, I would've freaked if the boost readings were all over the place, but it's not the case. Everything is reading fine...

i'm so confused...
 

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Is this td06h or td05h also what brand turbo and boost controller are running. Sounds to me like you are using the stock solenoid which deff give problems. Get the perrin EBCS.
 

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520hpSTi said:
yup the stocker is only good to 22psi i think and 1.8 bar > 22psi..i think.
Yes to the first part, and 1.8 bar is almost 26.5psi, which is waaay above what the ecu and stock solenoid can handle. This is not news - competent tuners already know this.

You need standalone, programable boost control amigo...and your tuner is mistaken if he thinks a 38mm tial EWG can't handle whatever a 20G can throw at it. There are guys using much bigger blowers with that wastegate and they're not having any problems dumping excess boost.

Using both wastegates is just plain goofy. All he's done is throw in additional variable that will make predictable [and repeatable] boost all that much harder to achieve. Not only that, but you give up all the spool-up benefit of having an EWG. Weld that puppy shut, get a good EBC, progam in a good safe map or 2, and you're done.

Oh yeah, there's one other thing I'd also suggest changing...but it isn't mechanical. ;)
 

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Flycaster said:
Oh yeah, there's one other thing I'd also suggest changing...but it isn't mechanical. ;)
Good advice..
 
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