I did start having boost creep after installing a tubular O2, but I attributed it to my high pressure actuator or possibly a misadjusted actuator arm. Anyhow, when I put my car back together with the coated turbine housing and manifold, I'm going to play around with it and hopefully resolve that issue. It's tough to play with the actuator adjustment when you have a heat shield over the actuator arm that you can't access without removing the radiator!

 

+1 Ive been getting boost creep in 4th gear once in a while also. I see it going from 1.5 to almost 1.6 and then the weird thing is that i hold 1.5 all the way past 7k with the stock blowoff valve! I tried adjusting the wga arm but no luck

 

In the DSM world, if you are experiencing boost creep, the most effective way to fix the problem is to port out the wastegate hole and/or get a larger flapper. This will ensure a high flow through the waste gate bypass and will help with boost regulation.

 

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That is true... in the DSM world. But this is the EVO world and that will not fix this. The wastegate hole(s) and flapper are plenty big enough. This problem is arising from the Ebay 02 housing's hole that is made for the wastegate exhaust to go into the regular exhaust. The hole is just too small. If you were to take off the 02 and open it up, that would fix it, but who the hell wants to do that? Not I.

Also, the creep people are experiencing is very minimal and not detremental. If it was going fom 22-23 up to 26 or something and holding there thatd be no good... but just in a high gear going up to 24 for a split second isnt hurting much. My car is hauling *** since my last tune which included the 02 so its definitely not hurting me.

 

Maybe speaking of boost spike.

There is no way it is creeping on a single flapper 10.5cm2. I have not heard of creep on even the 9.8cm2.

 

+1

 

Boost creep is the rising of your boost due to not enough exhaust bypassing. For example, you set your boost to 22psi. you nail it, and it goes to 22.. then 23, 24, 25 and its climbing as RPMs climb. It can be very dangerous for obvious reasons.

Dont confuse it with boost SPIKE which is just when you initially go WOT your boost might jump to to 25psi lets say then settle to where you have it set like 22psi. That is usually not harmful and can actually help your torque out a lot.

What I am experiencing is very minor boost creep with the new Ebay 02. Its minor though so I really dont care. Its not affecting anything negatively on my car.

 

Porting the o2 housing was what I was refering to. If you are too lazy to get your o2 housing ported then don't complain about boost creep.

 

Thats what happens to me exaclty, it will jump to 1.4 then climb to 1.5 maybe 1.6 as the rpms go higher and then comes back down. The weird thing is that it does it ocasionally not all the time

 

You said "the most effective way to fix the problem is to port out the wastegate hole and/or get a larger flapper."

How is that referring to the 02 housing. That has to do with the turbine housing.
Porting the 02 housing does not apply in this situation. We are talking about EVO 02 housings. No one gets creep with an EVO on a stock 02 housing so therefore porting does not apply to that.

The Ebay 02s are much larger than the stock 02s, even ported they are still bigger. The problem SOME are having, like me is that the little hole that allows the wastegate exhaust to combine with the turbine exhaust is too small. Its a minor problem no one is gettng in a huff about it.

 

I've got an EBAY O2 housing and have not experienced any boost creep.

 

Yes, I originally started getting the creep in 4th gear at 22psi gradually climbing to 25-26psi.

 

I've been thinking about this all day at work. From what I see those who have the ebay housing seem to be dynoflashed and the reason I mention that is this. I installed the O2 housing and the exhaust back in early January and experienced no noticeable creep. I never did any really long 4th gear pulls but I didn't notice any in 3rd. Well the Sunday before the original Charleston Sc tune I installed my walbro 255lph fuel pump and my AEM intake in anticipation of the upcoming tune. Only after installing these parts did I notice the major creeping issues. I have just been wondering if the installation of these parts has screwed up the fuel delivery so bad that it could be contributing to this problem. Perhaps unburnt fuel is igniting in the manifold, timing is being pulled terribly and causing the combustion to happen late enough to enter the manifold, EGT's possibly skyrocketing, etc....Perhaps it has nothing to do with it but it has just been on my mind and just was wondering what others may think of this theory. I know its far fetched but we all know what an untuned intake can do to an Evo. I'm waiting on my Forge Unos MBC and I may test these theories over the next few days. Maybe put the stock intake back on, go back to the stock pump and see what happens. What do you guys think???