Boost creep on t-25

[crashed97tsi]

Hey guys

I searched for oost creep and found out that on the 14b its very common after a dp and 3in catback. My questions is should it happen with the t-25 too. I creep from 15 psi top 18+. I've read that the only way to fix this is to take the o2 housing off and port and polish the WG and housing. Is this correct? Do i have to take the whole turbo and exhaust manifold off to get the o2 housing and wg flapper ported?

The parts I installed was an apexi GT dp And a RS*R catback exhaust

ANy help is appreciated

Thanks
Dan

edit: I was looking around and saw that the evo 3 o2 housing would work. Does anyone know if i could leave it unported or should i port it? Also, do I have to take the turbo off to install an o2 housing?

 

[97GSXAT]

I had boost creep on my 99 GS-T I had with a HRC 3" DP w/02 eliminator, 3" random cat, and 3" Greddy PE. Mine was set just like yours, around 15-16 psi and cept up to 18 psi or so in the high gears.

As far as the evo 3 manifold goes, for the T25 the 2.5" is more than enough flow for that small ass turbo. You wouldn't need to port it if you plan on just using that turbo for a while, although if you are thinking about upgrading soon, do yourself the favor now and get it ported before you decide otherwise and have to go in and remove it.

 

[crashed97tsi]

If you got the o2 elim. dp, why did you still have creep? Did you have to port the wastgate flapper? I am planning on getting a agp t28 so I guess i'll just get it ported now.

Thanks for the reply

 

[97GSXAT]

Still had boost creep because the exhaust system was so free flowing that the sorry ass flapper couldn't expel enough gas to maintain boost levels. I had the DP in the thought I was going to upgrade my turbo, then I actually realized I'd be wasting my money to get more power to be able to use less of it and bought the AWD

 

[crashed97tsi]

So the flapper and WG passage is the real problem behind the boost creep then. I'll have to port that then. Any idea if this can be done without removing the turbo?

Thanks again

 

[Brandon92DSM]

Originally posted by crashed97tsi
So the flapper and WG passage is the real problem behind the boost creep then. I'll have to port that then. Any idea if this can be done without removing the turbo?

Thanks again

yeah the O2 housing wont make that big of a difference compared to porting out the passage and pressing a bigger flapper on.

I wouldnt recommend trying to do that with the turbo still bolted to the car.

 

[crashed97tsi]

cool, I have an air compressor and a air drive. I rather not have to take apart the turbo to put a bigger flapper on. Would it help to just port the passage?

thanks again

 

[Brandon92DSM]

Originally posted by crashed97tsi
cool, I have an air compressor and a air drive. I rather not have to take apart the turbo to put a bigger flapper on. Would it help to just port the passage?

thanks again

maybe, but the whole point of the bigger flapper is so you can make a bigger opening around the edge. if you make the opening bigger but keep the small door you might have sealing problems, which woulndt help you either.

Im pretty sure you dont have to "take apart" the turbo to install the new flapper. Its hinge is just heat pressed onto the rim area of the WG passage.