02s in header
 

How far from the end of header should the 02 be placed

Re: 02s in header
 

most are as far back in the collector as you can get,, but a true reading should be in the primary tube of the leanest cylinder for your combo
collector readings will be leaner than in a primary tube ,,so when doing a dyno session apples for apples
if your on the dyno use the same sensor location

Re: 02s in header
 

Two inches beyond the merge. If in SS, you want them pre the pan evac.

Re: 02s in header
 

To add to what Sean said, 2" beyond the merge and it helps if you have somewhere in the neighborhood of 14 to 18" of collector beyond that.

Re: 02s in header
 

Within 20 inches of the exhaust valve will be more accurate see less fresh air.

Re: 02s in header
 

Tagging onto this thread. I put a different set of headers on my car that use slip tubes. I noticed the tube my sensor is in is leaking slightly. What can I use to seal it?
Kelly

Re: 02s in header
 

Permatex offers a high heat/sensor safe sealant.

Re: 02s in header
 

My are 9 from the end of collector

Re: 02s in header
 

Mine are about 4” from the end. Never dynoed it, found the happy spot (fasted tune up down the track) and monitor it now for changes.