Keith Williams building an O2 sensor for carb tuning
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Keith Williams building an O2 sensor for carb tuning
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!!!
Thanks Keith!!!
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67 SRL311-00279-resto project
Stock '72 240Z-Blue
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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.
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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SRL 311-01633
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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
keith
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I think there is a link to this oxygen sensor write up somewhere.
http://www.jetlink.net/~okayfine/su/airfuel.html
Ray B.
http://www.jetlink.net/~okayfine/su/airfuel.html
Ray B.
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Same problem with me and I'm using Mozilla Firefox 2.0.0.11 

Nissanman, just trying to help.
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RE:Keith Williams building an O2 sensor for carb tuning
I will take a look at the formatting.
Steve
Steve
66 Stroker-Going Orange
67 SRL311-00279-resto project
Stock '72 240Z-Blue
2002 Ford F250 7.3 Diesel 2WD Hauler
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2009 Smart ForTwo Passion Coupe
2013 Fiat 500 Abarth
67 SRL311-00279-resto project
Stock '72 240Z-Blue
2002 Ford F250 7.3 Diesel 2WD Hauler
2008 Toyota FJ Cruiser
2009 Smart ForTwo Passion Coupe
2013 Fiat 500 Abarth
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just print
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.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.
Phil
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Re: Keith Williams building an O2 sensor for carb tuning
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
Current Cars:
-1999 Porsche 911 4/98-build, 3.8L M96
Current Cars:
-1999 Porsche 911 4/98-build, 3.8L M96
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Re: Keith Williams building an O2 sensor for carb tuning
I fixed the link. It had been moved to the tech wiki and never updated.
S
S
66 Stroker-Going Orange
67 SRL311-00279-resto project
Stock '72 240Z-Blue
2002 Ford F250 7.3 Diesel 2WD Hauler
2008 Toyota FJ Cruiser
2009 Smart ForTwo Passion Coupe
2013 Fiat 500 Abarth
67 SRL311-00279-resto project
Stock '72 240Z-Blue
2002 Ford F250 7.3 Diesel 2WD Hauler
2008 Toyota FJ Cruiser
2009 Smart ForTwo Passion Coupe
2013 Fiat 500 Abarth
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Re: Keith Williams building an O2 sensor for carb tuning
Thanks!
Simon
Current Cars:
-1999 Porsche 911 4/98-build, 3.8L M96
Current Cars:
-1999 Porsche 911 4/98-build, 3.8L M96