o2 housing exhaust and boost leaks

[auker1]

ok so i found an exhaust leak between my o2 housing and my downpipe.the o2 housing is stock but i think the downpipe is aftermasrket because the welds do not look professional. i have already installed a new gasket and it has destroyed it. its a rather large leak. im wondering if i put a stainless o2 housing on it if it will mate up better? also my turbo exhaust housing is cracked, could this cause a problem and/or a leak? also i did a boost leak test and found a leak that seems to be coming from the intake gasket. i installed new intake gaskets like a month ago. is this a common boost leak area?

 

[habitatguy187]

1. Sounds like you might need a new downpipe.

2. Get pics of turbine housing crack

3. If by intake gasket you mean the gasket at the throttle body and intake manifold, then yes it is a common leak. The best thing you could do is get a throttle body barrier gasket, they're thick, reusable, and stop heat soak. Next best thing and what most people do is use an rtv type gasket of some sorts. I prefer the gm version, works amazing, but it's a little more expensive at like $14 a tube or so.

 

[My1GLaser]

Is it the stock O2 housing? I believe that an Evo3 O2 housing has a slightly different angle and can cause a problem.

Make sure the exhaust gasket has a fire ring. There are some that are a double layer that work to seal the space better. However, depending on the gap it has to seal, it will eventually burn those up too. I actually switched to a 3" copper gasket cause its reusable. I have had my DP off so many times to replace driveline parts that I got tired of buying new gaskets!

I always spray my TB gasket with a coat of copper spray.

 

[YZFR1]

On an evoIII housing you need to tighten the bolt closest to the turbo first and than do the other one. That gives it the best possible seal.

 

[auker1]

im sure its the stock o2 housing. yeah i think i just need a new downpipe cause it looks like it was made by someone and not manufactured. so ill try a new downpipe that way i know what i have. the boost leak is coming from where the intake manifold mounts to the head. not the throttle body gasket.

also any suggestions on a good down pipe? im not looking for something to push major horsepower. im looking for a max of 350hp goal sometime in the future.