Ok In the past on my Evo8 engine i had the same mod's as far as exhaust goes, SS tubular manifold, SS o2 housing, 3" tbe.

Did a evo 9 engine swap.....

Put the bigger turbo and the new IX engine, and now i have boost creep.......... I though Creep was caused by lack of backpressure not more or im just confused please inlighten me


This is what is happening......

3rd gear, WOT..................... pegs 21psi~ around 3500give or take , holds until around 5800 then slowly rise's to around 24 but never goes over 24 to redline.

Could this be something besides creep because i though creep just keep rising?

 

Set a manual boost control to 11 psi and floor it slowly in high gear. It should go to 11 psi and hold it pretty well. If it starts to slowly climb over 11 psi as the rpm's get high, that's "creeping". The boost creeps higher at high rpm's because there's too much exhaust flow for the wastegate hole to bypass.

Going to try this and see what the outcome is.



Ok did this hits 11psi from lower RPMS and it rise's to 13-or 14psi doesnt hit the 15psi mark so i dunno guys its some weird *** creep

 

Try taking any boost controller out of the equation all together and run the line from your boost source directly into the wastegate, ~12 psi. If it creeps then the W/G actuator is probably not functioning correctly thus the flapper door isn't opening to despell all the gases necessary out of the exhaust and in turn it's creeping.

 

wont that not work with me having the restrictor pill removed from the lines?

 

The restrictor pill is nothing more than pinching the line or creating a leak before it gets to the w/g. thus it will make more boost than the actual w/g spring allows.

Try it out if it spikes to a certain amount and holds to redline or dips off then your fine. If it spikes then slowly creeps up as rpm is increased then something isn't right as the exhaust gases aren't being directed out of the gate properly especially in the upper rpms as there is more exhaust flow.

 

mine creeps on spring pressure with the green, and it is not the actuator, we have already loosened it till it is about 1 turn from sliding on the pin at rest. It has been verified to open all the way while on the dyno. My problem is the gate cannot bypass enough flow in the midrange.

This could also be related to the ebay 02 housing, if you look inside one there is a passage from the gate side where it joins the main side that could have some variation from unit to unit.

 

mad VIII: Do you have the stock IX actuator or the FP HD unit?

 

Not sure, I did not pay for the hd actuator, but I was thinking they shipped it with one because of the midrange creep, however, we took a couple turns out of the turn buckle so it will just about slip right on the pin. No change.

I really think the reason some of the greens have the midrange creep has nothing to do with the actuator, but rather the style of hotside used, since there are two choices, the dual flapper and single flapper.

To be honest, I don't recall which I have, but I do know If I wanted to stay with pump gas only boost levels, I would be pulling it off to hog out the wastegate port.

 

So would putting the stock o2 housing fix this problem? I would think it would be worse since the stock o2 housing is smaller area of flow inside.

 

Wow, I really thought I told you what to do in the last thread you made about this a couple of days ago.

 

Ok I did, I thought I was going crazy.......

https://www.evolutionm.net/forums/sh...d.php?t=304163

 

I work 12-14 hours a night, and there is some drinking invloved lol so i probably did


I'll throw the stock o2 housing back on and see if it changes.

 

So just out of curiousity, if i do replace my o2 with stock and i still have creep then what? check the mbc and the wga?

 

ever get this figured out? I am having the same issue since yesterday. All i did was replace the stock WGAwith a Forge Unit. I'm hoping i just need to adjust it.

 

Nah i just turned down the boost, and sold it eventually.