O2 sensor placement

[Tom Cloud]

>How close does an oxygen sensor have to be placed to the manifold to
>reach the operating temp of 600 degrees F?

not so important for HEGO .... I use a non-heated EGO.   have shorty
headers with bung welded about 4" below collector.  Gets to temp
in about 8 or 10 seconds (don't know about winter -- haven't
had it in but a couple of months).  cast iron manifolds will
hold heat better probably allowing a little more distance.  If
you get too far back, output will drop when idling (non-HEGO).
My '91 F-150 has a 4-wire HEGO a good distance from the ex-manifold.
 .. down under the truck just in front of the first cat.

Tom Cloud

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