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Discussion Starter #1
so how can we stop boost creep besides porting the turbo. will a catback cause problem, will it help. what about dp and cat back. what about stock dp and 3" cat less back. what about full tbe with boost controller. i dont want to start a huge debate becuase im sure everyone has a diff opinion but almost everyone agrees that a full tbe causes creep. so any help would be great as im going to be in the market for an exhaust soon. after i get the car next week ofcourse :). thanks in advance. ryan
 

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Boost creep is caused by your wastegate being too small, the only way to cure it is by porting the wastegate. The more you free up your exhaust the more you will creep. I've heard that Guru has success with no creep with a DP and a stock exhaust but you may want to search for his posts to be 100% on how he does it.
 

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Yes ... only REAL fix is ported wastegate, as THAT is the problem. I am having a lot of stuff done today (eibachs, downpipe wrap, etc) and while hes doing that Im goin to have him take the turbo off and mill it out with a machine this time (instead of using a dremel). You can also buy a exhaust with a silencer built into it, as that will create 'some' backpressure as that is what you lack with a catback (the cause of the problem) although thats not a fix.. as who buy an exhaust for the silencer to be put in it? Anyways, an EBC will somewaht help, a silencer inthe exhaust will help, stock catback will fix the problem, porting the wastegate will fix the problem. Sorry there isnt a better solution.

Robert~
 

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Just be careful when you get it ported, read elsewhere about a couple people that apparently over-ported and now can't get their boost levels back up high enough.
 

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ya I will have to watch out for that... That is probably why he will end up pulling the turbo actually out and using a machine.

Robert~
 

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RadarOnPaws said:
Just be careful when you get it ported, read elsewhere about a couple people that apparently over-ported and now can't get their boost levels back up high enough.
How can that happen? As long as the wastegate seals when it's closed, you'll get boost...regardless of the size of the port.
 

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Do you name your cars?

thats just it... possibly an uneven port or too wide and presto... exhaust leak and no spool. That is why im having him take it out and use a machine. So everything is perfect and precise.

Robert~
 

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yup.. im dreading the labor costs of all this as my car has been in the shop a full day now :( , luckily i've done tons of businesswith him and he will hopefully cut me a deal. Man I neeed to invest some cash into tools and knowledge so I can do this myself... and get a lift lol.

Robert~
 

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I was planning on having deadbolt PNP my wastegate.....he's done so many of these I don't need to worry, right? I got sorta freaked when I saw RadarOnPaws post about overdoing it....
 
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I highly recommend Deadbolt. He does quality work, and is very professional.
 

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StuBrown said:
I was planning on having deadbolt PNP my wastegate.....he's done so many of these I don't need to worry, right? I got sorta freaked when I saw RadarOnPaws post about overdoing it....
**HINT** use a sharpie or something to trace around the Wastegate flapper... then dont get within 1mm (or at least dont go past the line) of it and you'll be fine.

Robert~
 

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You also can install a larger flapper like some of the 16G guys do and be a little more aggressive with the amount of material taken out.
 

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SOULUTION: buy bigger turbo! lol =)
 

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whoa ok this is the first time i heard bout over porting. I am about to have a guy port my wastegate and he ask how much i want to port it i was like i dont know, i heart people say 20%. So im asking yall how much should i get it ported,thanks for any reply
 

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Discussion Starter #17
so now im thinking, turboxs or godspeed catless dp with a high flow cat in the midpipe and then 3" the rest of the way. so i have one cat and the rest free flowing. what do youthink,. thanks
 

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sti_187 said:
whoa ok this is the first time i heard bout over porting. I am about to have a guy port my wastegate and he ask how much i want to port it i was like i dont know, i heart people say 20%. So im asking yall how much should i get it ported,thanks for any reply
tell him all the way without having it leak... you're going to need every bit out of there you can, but if he doesnt know not to over port to where it leaks... find another guy!!

so now im thinking, turboxs or godspeed catless dp with a high flow cat in the midpipe and then 3" the rest of the way. so i have one cat and the rest free flowing. what do youthink,. thanks
Cats arent good, but if you have to have some I guess that will work *shrug*. It'd be so far away though that I doubt it'd even clean, but would just be more of a block in your exhaust.

Robert~
 

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New STi for invoice - then mods

invidia is coming out with a hi-flow cat version of their current downpipe.
based on info from flat4engineering, it is based on the zerosports dp f/s in japan.
helix is also doing a hi-flow cat version.i would assume the same, since they seem to be identical to invidia.
stromung and xcceleration.com both have catted versions out now. i believe they both use random tech's new mini metal substrate cats.
the stromung is a divorced set-up, while the xcceleration is a 3" bellmouth.
 
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