Anybody using Narrow Band simulators on a LS3??

[rao]

I am new to Gen 4 tuning.

The car is a 2015 Chevy SS M6

I'd prefer to use my Innovate LC-2 wide bands in the stock front 02 bungs and feed the narrow band simulation output to the PCM. I have done this in the past on Gen 3s and been happy with the way it worked.

I noticed that the switch points on the LS3 are very different



which makes me question if there is anything about the front o2 sensors that would make NB simulation a bad idea.

It is not a big deal to install new bungs for the widebands, but I prefer to simulate the stock o2 sensors if it will work properly.

I'd appreciate any thoughts or experiences with this.

Thanks.

[schpenxel]

I've done it on an LS2 before. I didn't like it.

Widebands are too slow to react and the narrowband output cycled quite a bit slower than the actual NB O2 that was still on the other bank. Also, the failure mode of the analog outputs basically makes it either go to 0 or 1V if there's ever any sort of problem with the wideband or controller. My Innovate MTX-L setup had a sensor error one day when I was traveling and it maxed out fuel trims before I got pulled over and switched it over to open loop because the analog output was stuck on 0V no matter how much fuel the ECM added. I guess eventually the car would have thrown some kind of DTC for fuel trims being too high, but in the meantime the car ran like absolute crap.

I much prefer just adding another bung and leaving the factory stuff alone.

From what I've seen E38's and newer seem to cycle even faster than the E40 I tried it on, so I really don't know how well it would work... I know I won't try it again and will just keep them separate from now on.

I eventually switched to a PLX setup and have been happier with it.. but I guess that's a whole other thread

[FunkedOut]

strange. I have a 2010 Camaro with an LS3 and my switch points are 450mV across the board. So are the max/min rich/lean values.
Furthermore, I tried to adjust them a while back and found they do not affect operation at all.
It's like the ECU could care less what values those tables have in them.
Maybe your is the same?

For what it's worth, I fed the E38 a NB simulation signal from my PLX and it was happy.

[schpenxel]

Narrowbands "cycle" within such a tight window barely rich / barely lean that changing the the stoich point in terms of mV doesn't seem to do a whole heck of a lot. Supposedly on the gen 3 stuff it made a bigger difference.

I've messed with the settings too some but never saw any real changes. But when you think about it.. narrowbands are switching with changes of only 1 or 2% richer/leaner than stoich, so it's not like there's a whole lot of range to work with.

[rao]

Thanks for the responses.

I never found the response time of the wide bands to be a problem, in fact using the wide bands solved all of the problems associated with header o2 sensor placement, which was handy

I do recall reading that the gen 4 PCMs didn't do anything that could be observed with the switch point voltages, on the gen 3 they made a huge difference.

[FunkedOut]

that's all I needed at the time; 2% leaner, so my NB's would match my WB.
I logged NB mV against WB and found that ~150mV switch point would've been perfect.
updated tables and logs showed no change.
set the switch point to 30mV and operation stayed the same.