Im about to install my aem wideband and the instructions say to mount the sensor 18 inches from the exhaust port but my cat is less than that but i cant mount it after the cat. If i mount it closer is it going to be too hot for the sensor??

 

huh?

 

Ditch the precat.

 

+1

You will gain power by getting rid of the precat as well.

 

His car is a California-spec NB (presumably a '99-'00 since he's asking this specific question) and on those cars, the exhaust manifold is a short little cast-iron piece (almost exactly like a Bell turbo manifold, but with the outlet pointing down) and there's a catalytic converter bolted directly to it.

Thus, if he wishes to install a wideband O2 sensor on this car, he must install it very close to the exhaust ports on the head, which is contrary to the usual advice. If he does this, the sensor will explode and we'll all be killed.


Honestly, I have no idea whether this will work. You could use an extension and fix a heatsink to the end of it. Maybe it'll work, maybe it won't.

Try this: http://www.innovatemotorsports.com/x...cat=250&page=2

 

I was planning on ditching it when i go turbo in a month or so but i wanted to install my wideband and megasquirt before so i could learn how to tune and the like. Oh well.. Thanks guys

 

If you still want to be able to tune in the mean time to learn, you can pull the pre-cat off and gut it, put it back on, and put the wideband just downstream of where the cat was.

 

can you tap threads for a sensor on the exhaust?

 

No. He should have a bung welded on by the local muffler shop (or put it in a pre-existing bung).

 

If you decide to run a parallel install or keep both o2 sensors (for whatever reason) you can pick up a 99-00 federal emissions manifold for about $35, extend the wires yourself (or buy the racing beat race header kit if you want to keep your wiring neat), and weld in 2 o2 bungs (one for the secondary o2, one for the wideband).

But then again, if it's only for a month and you ditch it anyway, it may not be worth the $45-$120.

 

The factory rear O2 sensor is in the downpipe, between the pre-cat and main cat on a CA NB, so you can just put the wideband in the existing bung once the pre-cat is gutted.

--Ian