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Boost Creep - Getting too many opinions

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Old 07-27-09, 07:34 PM
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Boost Creep - Getting too many opinions

Rumours has it that i will be getting boost creep when i replace my original precat and downpipe with "test pipes" (no cat).

What are the measures i need too take too make sure that my car is running neither rich or lean or boost`s too much? Does changing the downpipe and cat mean that i gotta do a shitload of other work too?
like buy a new boost controller instead of the cheapassvalve controller i got now, and a new turbo so i can replace the screwed up internal original wastegate by replacing it with an external one? or maybe its just the spring on the original one that is screwed?

I get so many confusing opinions on all of this...
Old 07-27-09, 07:44 PM
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Having a "wide open" ex. will have little back pressure, this will cause the boost creep, boring out the stock-tinny *** wastegate will help alot, im running a Apexi Avcr boost controller and i love it!! those valves a ok but if ur stepping up, its a really good idea to upgrade the boost control.you could have a shop bore out the wastegate to a large amount if u wanted. i took mine to a machine shope and had the guy bore it out just slightly under the size of the flapper.

anyway YES openning up ur ex., u WILL have boost creep. and YES it would be a very good idea to upgrade the boost controller!
Old 07-27-09, 08:03 PM
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Originally Posted by OutCold
I get so many confusing opinions on all of this...
that's because it depends on a bunch of things...

for example a 2.5" DP with stock mufflers wont creep, while a 3" DP with a better flowing muffler will.

personally i had no trouble running a full 3" system with an s5 turbo and no boost control (this includes the factory solenoid!), on a cold night it would run 7psi instead of 6...

just be careful, and use your head
Old 07-27-09, 08:56 PM
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And by getting a boost controller i need a remap?
Old 07-27-09, 09:02 PM
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Originally Posted by j9fd3s
that's because it depends on a bunch of things...
+1

Originally Posted by OutCold
What are the measures i need too take too make sure that my car is running neither rich or lean
Make sure the fuel pump has proper voltage, or install an aftermarket performance fuel pump.
http://fc3spro.com/TECH/MODS/preliminary.htm

Originally Posted by OutCold
or boost`s too much?
- To keep it from boosting too much, do NOT use a boost controller.

- If you do notice boost creep, you can port the wastegate:
http://fc3spro.com/TECH/MODS/TURBO/wgp.htm

Originally Posted by OutCold
And by getting a boost controller i need a remap?
Not if you keep the boost 10psi or lower. Other than that, you may want a fuel computer. I have seen up to 12psi on the stock computer, but it's probably not such a great idea.
Old 07-27-09, 09:15 PM
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You should just port the wastegate if you have an S4 turbo, S5 you might be able to get away with it. Here is a pic of my S4 wastegate before & after. I took mine to a machine shop to do the work, but you can do it yourself too.
Attached Thumbnails Boost Creep - Getting too many opinions-wastegateb4-after.jpg  
Old 07-27-09, 09:30 PM
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Lucky me got an S5 and im running stock turbo @ .6 bar , in other words no extra power except from the streetport has been taken out of it.
Id might get away with just turning the controllervalve down one notch or two if i notice creep, wich brings me too my next question, how would i notice?

I just ordered Defi links so i guess those will help when i get them installed
Old 07-27-09, 09:45 PM
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Boost controllers cannot lower boost. You will notice boost creep when your boost goes up to like 10 or more. If you creep too much on the stock ECU you will hit boost cut which is bad. Creep too much on a cold night and you could lose your engine.
Old 07-27-09, 10:00 PM
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or get an S5 turbo they have dual flappers and i never get boot creep with 3" pipe and street ported

but yes port that little flapper and wield a blocker plate like the pics its the best way!! it dose not take long to fix either.
Old 07-28-09, 01:34 PM
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u wont hit fuel cut with a fuel cut defender. my electronic boost controller can help prevent creep, it has two settings "A setting (used for my high boost) and B setting (used for town cruising)" and on those two settings it has duty cycle and boost control.

i have on both A and B the duty cycle and boost turned up as high as it will go for Revs 1000 thru 3000, to help with the lag a bit.
then have it set to a level were i want to run the boost, if i see a fall in boost i raise the levels. if i see creep, i drop it a little ive havnt had any problems with this set up period, ill fly to Norway and bring my car to show u lol

ull know ur creeping if u have ur boost set for .6 bar and u see the boost gauge "creeping" from .6 to .65 to .70 to .75 to .80
Old 07-29-09, 02:31 PM
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Im running the PFC
Old 07-29-09, 02:41 PM
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on my s5 turbo i never got boost creep. just keep the stock intake. if you replace with 3"in straight intake it will creep.
Old 07-29-09, 02:44 PM
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my s5 turbo with ported wastegate still creeped like hell with straight through exhaust, porting, FMIC

I never fully controlled boost under all circumstances until I got a Tial 44mm external wastegate
Old 07-29-09, 02:51 PM
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in not reallyeducated on the pfc systems, do they even have fuel cut?
if u plan on keeping ur boost at .6 bar getting a elec. boost controller will help alot!!
espcially since u are openning the ex.
u WILL need to:
-bore the wastgate
-and control ur boost(if u want to keep ur cheap valve, or get a elec. boost controller)

im not sure y someone would tell u NOT to use a boost controller.. ive never seen a time attack machine thats boosted, not running any sort of boost controller... i dont think it would be wise to let that old actuator decide what BAR you want to run...

the ApexI avcr, wat i use, lets me keep my boost at the level i want it, i get no spike, and no drop in boost levels

i do have a slight creep, but i didnt do a big bore on the wastegate. and i would recommend going as big as u feel comfortable with
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