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leadfoot · Posted: Sun Aug 27, 2006 12:18 pm Post subject: Oxygen Sensor Location

From the pics in the 924 Parts diagrams the o2 sensor mounts in the outer downpipe tube, if I am mounting an aftermarket wideband sensor is there a better location??
I have seen other manifolds where they place the sensor in the join between the two collectors (at the 4 into two end) so that the sensor can pickup both sides of the manifold... is this a better option??
Thanks...
Leadfoot
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1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

Min · Posted: Sun Aug 27, 2006 12:48 pm Post subject: Re: Oxygen Sensor Location

Ozzie · Posted: Sun Aug 27, 2006 5:14 pm Post subject:

I thought the ROW cars didn't have the O2 sensor?
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Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
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leadfoot · Posted: Sun Aug 27, 2006 5:27 pm Post subject:

Got any pics??
thanks
_________________
1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

Smoothie · Posted: Sun Aug 27, 2006 11:51 pm Post subject:

Sure, picking up the O/P of all 4 cylinders has to be more useful than just 2.
You probably already know, but o2 sensors need to be at a high-enough temperature to give reliable readings, so unheated sensors are more position dependent (have to be mounted closer to the engine). Heated o2 sensors can be mounted farther downstream. (This probably accounts for why Porsche chose to put their unheated o2 sensor where they did. I'm sure if they were using heated sensors, they'd have placed them more downstream to pick up all 4 cylinders.)
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"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

Min · Posted: Mon Aug 28, 2006 2:29 am Post subject:

leadfoot · Posted: Mon Aug 28, 2006 11:33 am Post subject:

I got locked out of my photo acccount Min so I'm ok now with pics...
So if I'm using a heated sensor then putting it in the start of the 2.5inch collector would be the best spot?
I'm using a Bosch LSM-11, apparently there are better sensors but this is what the ECU is designed to use... they can take temps up to 850C or 1500F so mounting in the cast iron manifold and drilling inbetween the two collectors here might be a better location..

the only consideration is that it is reccommended to mount vertically between the 10 o'clock and 2 o'clock orientation and this would more likely be around 9 o'clock...
Leadfoot
_________________
1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

Min · Posted: Mon Aug 28, 2006 12:56 pm Post subject:

Mount it further away than that, One of the big problems wideband sensors can have is overheating, mount it down under the car.
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Custom means it didn't come from a box.
1980 n/a with EDIS and Megasquirt II Injection. 7 different colors and counting.