02 sensor extension question

[randeez stable]

I have some 02 extensions for my headers. I plan on stacking them by 2. ( they are each about 1" long) Anyways, the hole through the middle is just over 1/2" Im making a restrictors for the ends to let less exhaust gas get to the rear sensor.
What size hole would be best to put in the restrictor plugs ? Im thinking about 1/4" but not sure.

 

[OneQwkStang]

Huh

 

[randeez stable]

Huh

The extensions come with a hole in the middle.It is large enough to clear the sensor probe ( end) . I want to restrict the amount of exhaust flow that the sensor actually sees. Many of the extensions ( spark plug anti fowlers ) have a smaller hole in the end. Guys drill them out to accept the 02 sensors. The ones I have are already drilled out to accept the sensor ends and I want to make plugs for the ends to restrict how much exhaust flow actually reaches the sensor.
There is a company who sells extensions, with 3 different orifices for the end to tailor the flow.
Making restrictors isn't a problem for me as Im a machinist. All I want to know is how big the hole should be in the very end of the extension , where the exhaust flow enters.

Make more sense ? Just tell me what sized hole to put in it, and Ill do that.

Ill make some for you to Qwk , if you need them.

 

[randeez stable]

Here are some pictures, to better clarify. At present, I have a 1/4" hole in the end of the sensor extension that screws into the H pipe.

 

[fdjizm]

Those are called non-foulers.
You leave the last fouler as is, it already has a hole in it.
I passed emissions with mine, 1/2" through the first one and leave the second one alone.

 

[randeez stable]

Those are called non-foulers.
You leave the last fouler as is, it already has a hole in it.
I passed emissions with mine, 1/2" through the first one and leave the second one alone.

Ive seen where some guys restrict the opening, because a lot of the non -foulers are restricted to less than the 1/2" size required to install the sensor.So they drill out the last extension, and leave the first one alone. And there is one company who sells non - foulers with different sized orifices.
Can it cause any problems if you restrict the opening size ?

 

[fdjizm]

By last fouler I mean the one that touches the pipe not the one that touches the sensor. you leave the hole that comes with it alone and small as is.
No it won't cause any issues, the o2 sensor is just "sniffing" less exhaust.

The 2nd o2's do NOTHING but check if the cats are working correctly, you don't need any different sizes, just drill it for the sensor size and leave the second one alone

 

[cbass]

I bought tiny little catalytic converters, work like a charm.

Sent from my SAMSUNG-SGH-I527 using Tapatalk

 

[cbass]

Sent from my SAMSUNG-SGH-I527 using Tapatalk

 

[fdjizm]

lmao wtf is that

 

[cbass]

lmao wtf is that

World's smallest catalytic converter!

 

[fdjizm]

it's so cute!!! keychain that shit.

 

[cbass]

Expensive keychain.

 

[OneQwkStang]

Why are you even bothering with this..shut the rear 02's off in the tune so they show up N/A on the OBD2 test.

 

[fdjizm]

And then you fail your OBD test, ask me how I know.

 

[OneQwkStang]

Not where he lives.

 

[randeez stable]

Not where he lives.

I thought I had to get it tuned with the sensors all on. That's why im thinking of installing the anti fowlers.
If the sensors are turned off, it will read a "not ready" which would fail the test. Correct ?

 

[Grabber Blue 5.0]

I thought I had to get it tuned with the sensors all on. That's why im thinking of installing the anti fowlers.
If the sensors are turned off, it will read a "not ready" which would fail the test. Correct ?

Incorrect. There are tuners that can turn off the codes but still have the readiness tests ready. The anti foulers are not necessary.

 

[randeez stable]

Incorrect. There are tuners that can turn off the codes but still have the readiness tests ready. The anti foulers are not necessary.

My tuner is well known and good. But where they are in Michigan, they don't have to go through the same emissions testing as I do in Canada. My tuner mentioned the non fowlers to me. Now im really confused.
So once I get the long tubes on, with my Procharger, what do I do next ?
I mean what do I do tell the tuner how to do his job ? Especially if he hasnt been tuning cars to pass OBD emissions ? Again, my tuner is not fly by night.

 

[Synyster06Gates]

And then you fail your OBD test, ask me how I know.

Not in Texas. I'm only allowed 1 not ready code. When I used American Muscles tune, I failed OBD2 because they way they do it makes it read "Not Ready". When another reputable tuner did my tune, he was able to make them show up as "N/A" as if they never existed and I passed easy.