Using wideband o2's in place of narrowbands?
You cannot wire the sensors directly to the PCM. Narrow bands are 0-1.0v signal output, and widebands are 0-5.0v signal output.
What you CAN do, is get 2 wideband kits, with 0-1.0v analog outputs, and wire them into the PCM. But, you still will only have a "narrow band" input to the PCM.
let you program the main output to be so. A cheap comparator IC attached
to the primary output could provide you the right signal, easy enough.
You want to watch the wideband signal conditioning, though; a lot of
filtering goes on and there's a lag that can destabilize the closed loop
fueling (I see transport delay stuff in the software but no idea how to
use it or if it's even appropriate to this).
I wonder how much heater current a narrowband can take and whether
a better approach would be to run the heaters, hotter. Like with a boost
DC-DC converter.
What screws your switching is not the cam, it's the headers. There are
some theories about ways to keep more heat (wrapping, shielding, open
the slots in the probe, use a standoff to cut conduction) but I just said
the hell with it and went back to shorties.
One thing I was working on, but never got to putting onto the collector,
was a bit of clothes dryer ducting cut with tabs bent to stand it off
from the collector wall 1/4" and a 1" hole cut in the center of the foot-
long segment for the sensor. Idea being that this would be like a
Thermos and let the local area be at exhaust gas temp rather than
halfway to ambient. Same idea as those anti-blue motorcycle exhaust
pipes. The fiber wrap can be bad for headers if you do it too close to
the head and they can hold moisture to cause rusting, but a shield
approach might net you some improved switching.



