Location of Wide Band A/F Sensor

[freds]

I've read Innovate's recommendations (2ft fom turbo etc.), or use heat-sink bung extender if too hot.

With the 818 setup with the FFR angle piece bolted to the turbo, then the stock Subaru down-pipe with cat and the short tail piece supplied by FFR....Nothing matches the standard installation guidelines.

Two Questions:

1. Where is the best location for the sensor?

2. If using the Innovate heat sink bung extender...which way should the dimple in one of the hex faces be oriented? Upstream, down stream or..?

Thanks

fred

[Rasmus]

1. Where is the best location for the sensor?
After the turbo but before the catalytic converter. When I tuned my WRX, I installed it about 100 mm from the turbine blades. Mostly because there was already a bung welded in my down-pipe with the correct threading. For me it was only a temporary install. Once I got my MAF (Mass Air Flow) table sorted to +/- 0.5% accuracy I uninstalled it.

I don't really know if you can get the WideBand too hot with a Subaru Flat 4 under normal tuning conditions. It's not like we're pushing the thing to pump 3 bars of exhaust gas through the turbine for 30 seconds until the turbine housing glows white.

[freds]

After the turbo but before the catalytic converter. When I tuned my WRX, I installed it about 100 mm from the turbine blades. Mostly because there was already a bung welded in my down-pipe with the correct threading. For me it was only a temporary install. Once I got my MAF (Mass Air Flow) table sorted to +/- 0.5% accuracy I uninstalled it.

I don't really know if you can get the WideBand too hot with a Subaru Flat 4 under normal tuning conditions. It's not like we're pushing the thing to pump 3 bars of exhaust gas through the turbine for 30 seconds until the turbine housing glows white.

Thanks that helps. I also don't intend keeping it active, but I have a new short block that needs to be run-in before I can get a real tune...and I am dead nervous of running too lean when I do those first miles, as I have a new Bora header, have ported some, removed the TG butterflys etc, so the original tune is unlikely to be close.

I'm not too worried about overheating the sensor during that time, but am curious about the heat sink bung's correct orientation. I see OBX has an Innovate knock off for about $30 less, so I might put one inn...can't hurt, I figure.

[CHOTIS BILL]

Auto Meter instructions state

“Turbocharged applications should have sensor installed 4-5" after turbo on the down pipe “

Bill Lomenick

[freds]

Thank you guys. Makes sense, and I believe!!!

Now who can tell me about the heat-sink bung extender's orientation. The section of it that extends into the exhaust gas flow has a radial hole near the pipe wall (which is in line with the dimple on the one flat of the hex). The other hole to the sensor is axial up from the end of the bung extender. The two holes make a passage through the extender for gases to flow through (past the sensor).
Either the gas is supposed to enter the upper radial hole and exit from the bottom hole....or the other way.
Innovate haven't got back to me on this and I imagined someone on the forum would know and pass on the info...before Innovate get around to it!

When they do, I'll post the answer.

fred

[philly15]

After the turbo but before the catalytic converter. When I tuned my WRX, I installed it about 100 mm from the turbine blades. Mostly because there was already a bung welded in my down-pipe with the correct threading. For me it was only a temporary install. Once I got my MAF (Mass Air Flow) table sorted to +/- 0.5% accuracy I uninstalled it.

I don't really know if you can get the WideBand too hot with a Subaru Flat 4 under normal tuning conditions. It's not like we're pushing the thing to pump 3 bars of exhaust gas through the turbine for 30 seconds until the turbine housing glows white.

ive always installed my widebands on my previous wrxs in the bung just after the turbo that most aftermarket downpipes come with. so far only one sensor stopped working, it made it 3+ years of daily driving and autocross on the weekends before it stopped working. we just had to replace the part that screwed into the bung, found it for about $50. i usually dont use the heat sink either. they do last quite a while in my own personal experience.

[Wayne Presley]

I put them after the turbo in the downpipe. Never had any issues.

[freds]

Thanks everyone!

[freds]

The dimple on the heat-sink bung extender faces the engine...per Innovate tech.

fred