O2 sensor upgrade?

[Big_ml_101]

Just bought my first DSM, and I've been reading up before I start digging into it. I've read a lot of mentions in passing about O2 sensors, and on the VFAQ's site I found this in recommended build path:

"10. A larger Turbo and opening up the O2 sensor passage. $700 to 1500
The Mitsu racing turbo (16g) seems to be a good choice. If you want more, go with one of the many hybrid turbos that you can get from one of the many aftermarket people. Dave B. can set you up with just about anything."

My question is what is the purpose of 'opening up the O2 sensor passage', what does it involve, and is and upgraded O2 sensor needed recommended? Thanks!

 

[WRXkiller92]

it means a more free flowing O2 housing, which is what connects to the exhaust side of your turbo and the O2 sensor plugs into.
the O2 sensor itself isn't upgraded at all

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for instance, one of those ^^

 

[LiquidX]

Porting out a stock o2 housing or going with a tubular o2 housing, as WRXkiller said, allows less restriction in the exhaust side of the turbo. A common upgrade is getting a Megan Racing o2 housing or even a Punishment Racing housing.

At this moment, I would stick with a recirculated housing (stock style) and not be too concerned with external wastegate setups yet. Down the road, you can always sell the pipe.

A major helper is actually porting out the wastegate inlet on the turbine housing and smoothing out the outlet hole where the gasket would sit between o2 housing and turbine housing. There is a terrible lip that the exhaust gasses hit when the wastegate flapper opens up.

If you have any other questions about it, generally doing a title search for wategate porting will show a good bit of info on that once you sort through it.

 

[Big_ml_101]

Thanks X, that was well explained. Appreciate it