O2 (wideband) with wastegate placement

[JNR]

I will be using an external wastegate that I was planning on re-routing back to my exhaust, eventually. I was thinking of doing this about where the DP bend is...

However, the bung for a wideband O2 sensor would be before joining the exhaust back in...I noticed the factory O2 housing (EVO 3, fwiw) has the O2 sensor placed to where the WG gases do not go past this; that is the 'regular' O2.

So, the question(s) is: On a WB O2 sensor, would it make any difference if the WG gasses do not pass this sensor and/or what does the O2 sensor (WB) read anyhow (percentage only); is there any advantage running it by there, for tuning and such?

Thanks,

John R.

 

The spot you're talking about is really too close to the turbo for a wideband o2. It needs to be installed past that, about 18" (not more) from the turbo. Weather or not this sensor sees wastegate bypass gasses should not matter one bit.

 

[JNR]

Yeah, I will be using a 'regular' O2 at/near the stock location on the housing and the WB O2 bung is installed on the downpipe, at around 12" below the flange, which would put it ~18" from the turbo outlet...I was just wondering if it makes a difference whether or not my wastegate gasses pass by this WB; sounds like it doesn't then...

 

[Polish]

They are still the same exhaust gases. Passing through the wastegate hole is not going to affect them.

 

[JNR]

'tis true, as it does not detect teh 'volume' of flow and I couldn't see how the % would change, provided there are no leaks. I wanted to verify that this is all it read and wasn't really different than a 'regular' O2 in that respect...Splittin' hairs, ya know /ubbthreads/images//graemlins/crazy.gif

 

[Rausch]

+1 it just percentages/ppm. if only 10% of teh exhaust gases passed the WB , it wouyld still function correctly......intheory anyways. so yeah, no worries...