After installing my Megan o2 housing and 10.5 hotside onto my VIII turbo, the boost slowly keeps rising in WOT until I let off.

Here are my current and only mods right now:
STM Intake
AMS FMIC
AMS LICP
Hallman Pro MBC
3" Turbo back
Megan o2 housing
10.5 IX Hotside
EVO IX BOV

I was told I should not be boost creeping with the Hallman MBC. Any ideas? The hallman is installed correctly and I did not have this problem until after the o2 and hotside install.

Thanks

 

Very common issue. Small turbo, why not let it creep? If you search "boost creep" on here you will find numerous similar threads.

I personally when using a stock framed turbo, port the WG flapper and eliminate the issue.

 

has ur hotside been ported? if not, then get it ported and like partyboy mentioned, port the heck out of the wg slots.

to rule out whether the mbc is bad or not, just run ur actuator's sgnal directly off the jpipe/in mannifold pressure, this way u should only hit 11-14 psi depending on the actuators spring load. if u hold 11-14psi till redline, then the conculsion should be that ur mbc is bad.
gl!

 

Nope. It has not been ported. Thanks bud!

 

ya iam having the same issue with mine and did all of the following except for porting the hotside:
1) boost leak check
2) swapped vacume lines
3) swapped mbc's
4) swapped 3 stock oem actuators
5) swapped o2 housings (currently have an innvedia on)

and will do the following:
1) slap on a forge actuator
2) port the hotside.

 

Ahh ok. I don't really even feel like taking it back off to port the thing to be honest. I will just deal with it haha.

 

happens alot w/ those o2 housings. you have to slightly adjust the wastegate arm. and yes the stock wastegate is adjustable, just do it very small increments.

 

Do you have any more details on this? As in which way to adjust it (turn it).

Thanks

 

Ya Ive herd of people porting or slightly enlarging the wastgate merge hole on the megan o2 housing to prevent boost creep.

 

hear ya man. I had to bust her open 5 times, but on the brightside, i can swap the o2 housing in almost 2 hrs now..haha

u will need a 13mm open wrench ( if i remember correctly!) to release the jam nut on the actuators arm, then turn the lil coupler where the pin that holds it to the flapper sits, and turn it maybe 2-3 turns to make the arm travel a lil longer.

I had to take the actuator off the turbo to get this done, it was tough doing it while its on the car.

 

i had this same problem when i tryed running lower boost. Turned it up to 20psi and no more creep.

 

I think that the jam nut is an 11 mm, which is about equivalent to 7/16".

 

Check the o2 housing where the wastegate gasses return into the exhaust, you may have to open the hole up a bit more if it doesn't match up well. Or just get an open dump and forget about spiking/creeping.

 

i had to do this after a megan o2 housing also.... first you remove the small clip holding the wastegate arm to the hotside. now that its free, you'll see the length dictates how much the wastegate will open. loosen the locknut behind the arm and now turn the arm (clockwise i believe) one turn. reattach then go for a drive. just turn increment will reduce or eliminate the boost creep. adjust slowly as it can wear out the wastegate internals.

only negative is you may notice a slight increase in spoolup.

another way you can get rid of boost creep is to remove the o2 housing and get the wastegate passage as its a big cause of boost creep.

 

Just take the downpipe off and port the o2 housing a lil bit