I recently swapped my stock o2 housing for a megan o2 housing due to a broken downpipe bolt in the stock housing. Anyway I've noticed that only it seems in 3rd gear the boost creeps to 25psi, past the set 19psi that I've noticed in other gears. My question is the only way to fix this issue to port the o2 housing? I've also heard about trying to change the pre-load on the wastegate arm to fix these issues.

 

Port the O2 housing also you can buy aftermarket waste gates or external to fix that kindda problems, and also what kind of hotside is your turbo.?

 

It's a 9.8 hotside, by porting it would just be the hole that connects the two exhaust flow together correct?

 

check this thread out , if you can you should send your turbo to 10.5 there are many companies that does that or you want to do it yourself? and get it ported aswell , as the O2 housing.

https://www.evolutionm.net/forums/ev...e-upgrade.html

 

Yup, that hole is too small in the megans and is causing boost creep. Port it. You might as well pick up a 10.5 hotside while you are at it, they are cheap and will give you some more hp.

 

Ive never had any boost creep with my evo 9 turbo and megan o2 housing. A 10.5 housing is your best bet