So while pulling my motor I forgot one step I was supposed to do...figure out where I could place the wideband so it wouldn't hit anything. I'm going to run a aem uego and stock ecu, so cant reuse the stock location.

I'm having a friend weld it at his school's race shop which he'll be at this sat, so I would like to figure it out for then rather than putting the car all together and test fitting.

Anyone running a second o2 sensor on a stock header that they could either share some pics or general placement guidelines?

If all else fails I'll eyeball where the header sits by referencing pics I have and go from there.

Car is a 1994

 

<p>I'd add it right before or after the stock bung.&nbsp;</p>

 

Has to be right before the cat. Too much closer and you'll cook it.

 

Thanks. DO you know what clocking it should be at to not clash? Im thinking 11 o'clock if you're looking from the front of the car into the bay.

Trying to "visualize" the space I have without having the motor there. Pics would help if you have any!

 

add it directly in the stock bung.

oh wait you bought an AEM so you cant... lol.

 

As vertical as possible, leaving clearance so as to not hit anything when the engine/exhaust moves. About 10 o'clock is a good compromise. You just don't want it pointing down so condensation collects in it. It isn't that critical. Route the wires up through the shifter opening, under the large boot.

 

I'll aim for that, and hope for the best.

routing through the shifter opening is a good idea, haven't heard about doing that one before. Any issues with wire insulation degrading though? Maybe if I do that I'll cut a relief in the boot, or take a punch and dent a groove into the trans tunnel.

 

I have been routing wideband wires through the shifter turret for years in multiple miata's. Never have I had an issue. Honestly on the stock exhaust manifold I would put it pointing straight up at the end by the flange before the cat.

 

Careful, you'll have to ensure a perfect seal at that flange, or you'll introduce air and get a bad reading. I'd put it ~12-18" away from a flange, pointing up.

I also have my wires going through the shifter turret, you will eventually wear out the wires. I put a small piece of copper tube around that area, then wrapped it in electrical tape. The shift boot can crush the copper, but it still protects the wire. That works, or find another method.

 

shift boot is best:

1. the sensor away from a turbo before the cat is ideal.
2. routing the wiring from the sensor in the exhaust to the controller is easy.
3. it keeps the controller under the dash and away from harsh environments where they fail.
4. there happens to be power and grounds at the dash.
5. the ECU is in the cabin for easy wiring.

 

I have never had an exhaust system that drew a vacuum and sucked in outside air... If you are talking about low pressure waves from the ports sucking in air from outside, unless he has an open pipe after the sensor it isn't going to back track into the system enough to effect the O2 sensor readings. Dyno shops just stick an O2 sensor in your tail pipe and get acceptable readings a few inches from open air. The only bad thing there is exhaust transit time from the exhaust ports to the tail pipe.

Keith

 

Welded 6" from cat flange, at 12:30 looking from rear. lets hope she fits!

 

Clears perfectly.