i've heard many people say that the best place to install any wideband o2 sensor is around 12-18" away from the turbo, basically almost at the end of the downpipe. my question is, i have a helix d/p and there is a bung on the bellmouth right after the turbo, and also towards the end as well. which one of the bungs should i use?

Use the one closest to the turbo. The one at the rear of the downpipe is for the stock rear O2 sensor.

for tuning i would put the sensor in the front location, it'll get better response there.

After the tune, if you're going to leave the sensor in for daily driving, move it to the rear of the DP location to preserve sensor logevity :)

ha ha!! i was right :) that's where i have mine, right after the turbo. thanks for reconfirming guyz :banana:

i have the helix dp and i wish they moved the sensor location for the wb back a littl bit

yup. it sits like 4-5" away from the turbo.

Sorry to spoil the party but I disagree. And so does Turbo XS and Innovate Motorsports.

Installing the Wideband sensor 5-6" from the Turbo doesn't provide accurate reading as the Turbulence from the Turbo skews the reading. Another is the sensor is designed to be operated at 750c internal temperture. The front bung on the downpipe is considerable hotter than the end of the down pipe.

Make sure you mount it on a slight angle and before a cataylic converter. Preferably at the end of the Down Pipe for accurate readings without the heat issues.

I suggest you read the manuals thoroughly.

^^^I agree and this is where I installed my O2 sensor.
http://i19.photobucket.com/albums/b181/Crazykevwrx/IMG_0099.jpg
Excuse the nasty lookin' DP. CV boot had a hole it it and goobed it :p

http://img301.imageshack.us/img301/9931/widebandeditedjj3.th.jpg (http://img301.imageshack.us/my.php?image=widebandeditedjj3.jpg)

I had mine installed about 9 o'clock across from my O2 since I'm catless. I was able to tune out the CL/OL jerk by just adjusting the fuel so I guess it's good!

I have mine a few inches further down that post 8. I think I'd rather put it further up and closer, because it is noticably slow at lower and moderate load. It isn't that bad full tilt, but I'd rather have some reassurance it isn't way behind. I'd probably go even closer that post 8 by a few more inches.

Mine's about as far back as you can go on the top of the DP before it starts to angle downwards... Yes I know it is closer to the turbo than recommended, and this presents a potential issue with the O2 sensor's internal temperature management. I made a copper heatsink for it to help combat this. No problems so far. But I've got the VW sensor, so if it goes out, at least it's cheap! :p