NOOB wideband AFR question
 

So I plan on installing a wideband AFR gauge and was wondering about orientation of the sensor on the down pipe. Does I mater if I put the sensor before or after the o2 sensors?

18 inches away from exhaust ports on N/A
36 inches away from turbo if boosted
Mount before cats if you have any or go catless
Mount AFR sensor at a 10 degree angle minimum
AEM recommendations

The distance varies by car/manufacture though but a good rule is somewhere between 16"-40" away from the engine... far enough away where you don't kill the sensor (overheating.) If your have a turbo place it further back on the downpipe for the same reasoning.

You can place it around the upstream 02 sensor. Just know, if it is behind any of the catilyic converters they will interfear with the readings. Also place the sensor on the topside of the exhaust so if the car sits, condensation will not sit on the sensor. 10-2 O'Clock postions work best depending on piping design.

Thanks guys, I forgot to mention I'll be FI

Also just out of ceriosity, did I see somewhere that the secondary o2 sensor is a widband?

Secondary isn't a wide band. I used the secondary spot until I could get a new bung welded in. I've got it between the primary and secondary sensors now.