Keith Williams building an O2 sensor for carb tuning

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S Allen
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Keith Williams building an O2 sensor for carb tuning

Post by S Allen »

Keith of Roadster Ranch and SU carb rebuilding fame has done a write-up on building a O2 sensor and using it to tune SU carbs. You can check it out here http://www.311s.org/pmwiki-311/pmwiki.p ... n.O2Sensor It includes a parts list with recommended sources. I am sure Keith will answer any questions you might have. Update: fixed the link....

Thanks Keith!!!
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Conner
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Post by Conner »

Great work, Keith. I've wondered about this before.
I'm no expert on this, but I'd be concerned that the 25 foot length of the wires from your sensor to your control box may dilute the voltage signal and give you a systematic under-estimate of the reading at the sensor. Obviously mounting the control box on the tailpipe is not acceptable (talk about a lot of walking back and forth). Maybe your suggestion of welding an O2 sensor bung into the first pipe behind the exhaust manifold would allow for a shorter wire. Then after everything was tuned you could screw in a plug to block the hole for driving.
This is a great step forward for tuning our cars, no question.
Andy Conner
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keith0alan
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Post by keith0alan »

The oxygen sensor output is a very high impedance signal. You draw so little current that the level loss is nearly undetectable (I squared R and all that stuff). Having the sensor mounted close to the engine has advantages. The benefit with the end of the tail pipe route is that I can stick it on any car that wanders by with minimum fuss. When one of my friends come by trying to get through the smog test this is one of the first things I drag out. It also works with Solex and other carbs.

keith

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Post by itsa68 »

I think there is a link to this oxygen sensor write up somewhere.
http://www.jetlink.net/~okayfine/su/airfuel.html

Ray B.
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RonDay
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Post by RonDay »

I just looked at the link to Keith's article, and the button text from the home page covers the left portion of the article text on its first page. This is on a PC running XP Pro, IE7. Haven't looked at it with Firefox.
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Post by Nissanman »

Same problem with me and I'm using Mozilla Firefox 2.0.0.11 :roll:
Nissanman, just trying to help.
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RE:Keith Williams building an O2 sensor for carb tuning

Post by S Allen »

I will take a look at the formatting.

Steve
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just print

Post by fj20spl311 »

RonDay wrote:I just looked at the link to Keith's article, and the button text from the home page covers the left portion of the article text on its first page. This is on a PC running XP Pro, IE7. Haven't looked at it with Firefox.
I had the same problem...I just printed it away, and it turns out that only the vertical dashed blocks obscure the article.....VERY READABLE.
Phil

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2mAn
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Re: Keith Williams building an O2 sensor for carb tuning

Post by 2mAn »

This link doesnt work... I would like to add an o2 sensor to my car soon so this bums me out. Where is there actually space to put it
Simon
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S Allen
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Re: Keith Williams building an O2 sensor for carb tuning

Post by S Allen »

I fixed the link. It had been moved to the tech wiki and never updated.

S
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67.5 Stroker-Purple
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Stock '72 240Z-Blue
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2mAn
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Re: Keith Williams building an O2 sensor for carb tuning

Post by 2mAn »

Thanks!
Simon
Current Cars:
-2003 Mini Cooper R50 - Daily Driver
-2002 Toyota MR2 - Dream Chaser