This can't possibly be the factory boost level...

[J2GK]

Normally "boost creep" is the result of long vaccum hoses coming from the manual boost controller. The best way to eliminate this is with "electronic boost controllers" like Blitz which handles boost levels more accurately. Not sure if piggybacks with boost control would equal the Blitz EDFC accuracy.

@J2GK

Now I know why your boost dropped. You are only supposed to swap out 1 side of the restrictor hose. If you replace the hose from the "other or wrong" side, boost will drop. But you're better off now with the boost controller.

   Yeesh, we only got electricity today.

   How much is the blitz edfc? I was initially considering an electronic boost controller but i figured mechanical would be better (less electronic voodoo that could go haywire). The car seems is already laden with enough technology that i sometimes feel like i'm not in control anymore . I'm considering dismantling the abs...

    As for the restrictor hose your right; i had gotten tired of the trial and error i was doing and just decided to get the boost controller.

   ...i still have alot to learn about turbo engines.

   Thanks for all the help guys! kitakits tayo sa carshow...

[Conan®]

I think the Blitz EDFC is around the 30th price range.

[rota wheels wrx]

Yup, when you get the hoses inverted, max boost drops. From experience, it will not go past .7 bar.

Here is the deal with boost levels. Subaru ECUs are fuzzy logic and learns as you use the car. It will also allow overboost up to 1.2 kg at full load on third gear for a short period of time before bringing it back down to 1kg. this is the reason why some people site 1.2 while others quote 1kg.

With regards to "creep", Tuners in the US counteract this by playing with something called the wastegate duty cycle parameter during remap of ECUs.

[Sc0oby]

jdm o4 sti is boosting 1.2 bar for a short burst then trail off at high rpm

[baby'zilla]

I think the Blitz EDFC is around the 30th price range.

i use the old blitz dsbc ( dual solenoid boost controller). got it 2nd hand for about 6k a couple years ago...

the greddy profec series is a good electronic bc option, not too expensive, except for the e0-1

[yellow jacket]

Manual boost controllers are more prone to boost spike than electronic type. Heat can affect the spring or valves of the manual boost contrler as it expand, specially when installed in the engine bay.