WB sensor placement

[BOTTLEFED]

I'm not sure if this is the right section for this question but...
I'm about to install my Innovate LC-1 w/XD gauge but I'm not sure where the best place is for the O2 sensor

I would like to get a reading from both banks without the hassle and expense of 2 kits
so I thought maybe the cross-pipe at the rear of the exhaust would give an idea of what both banks are doing

I'm just wondering if anyone has tried this location or if it is a bad idea

[Schulmann]

Unfortunately in the case of the Viper you have to have two WBOs. The PCM dates back from the stone age and doesn't provide any protection agains pinging. If you miscalculate your AFR, it is a matter of time before you blow up your engine.

If you have a NA Viper you can use a single WBO to survive.In this case place the WBO after the cross pipe. However you might have "self cleaning" issues. I would definitely use two wbo on modified engines.

In forced induction applications, I strongly suggest you to use two WBOs. If for any reason anything fails on one side of the engine you will have a quick feed-back and likely you will have the time to slow down.

Place the WBO as close as possible after the headers' collector. Myself, I have placed my WBO into the 2nd plug (in place of the second o2 sensor). I didn't have any issues but it is better to have it closer to the headers for self cleaning.

I have a friend who uses a single LM-1 WBO (not a permanent installation) on a Nitros application but he has stange issues He could have better results if he had two perm WBOs.

[dave6666]

I think he's trying to put in an A/F gauge, not run the PCM for engine management.

[BOTTLEFED]

acually just the sensor

I have a H-pipe/cross-pipe at the rear of the exhaust
I thought since it is the only place both banks tie together, it would give a reading for both banks - sort of

[dave6666]

Originally Posted by BOTTLEFED

acually just the sensor

I have a H-pipe/cross-pipe at the rear of the exhaust
I thought since it is the only place both banks tie together, it would give a reading for both banks - sort of

OK... A reading for doing what with?

And the crossover may not flow like the main pipes do.

[Schulmann]

Yes you can place it after the cross-pipe but there is no bung. However the cross-pipe doen't make big exhauste mixing.

What modifications do you have and what year is your Viper ?

If you get into serious tuning you will definitely need two WBOs.

[BOTTLEFED]

I would have a bung welded into the cross-pipe

I'm adding this WB in for tuning my VEC2
I've got headers, exhaust, smooth tubes, and I'm adding N2O right now
I want to add forced induction in the future

I just dont' want to clutter the interior with WB gauges
JackB suggested replacing the voltmeter with the XD-1

[DAMN YANKEE]

See your PMs

[DAMN YANKEE]

My humble opinion....

1. No, not that far back...ever. Cats? No Cats? Hi Flo Cats?
2. No, that meter is fun and pretty, but worthless for tuning. If you cant return it and just go with an LC-1, no problem, but the meter itself is eye candy and useless for tuning. You must log...see #4.
3. No, you don't need two WB, one WB & two bungs (one capped) will work fine.
4. You have more work to do and more to buy to really tune well.
5. If you go positive induction, there is more....

See your PMs...its great that you want to tune your own rig...its alot of fun and will make your car a monster.

[sctdev]

Two wide-band kits is overkill. We've tuned literally hundreds of dual exhaust cars using one wideband. Yes, you COULD try to lift IF you saw one bank going lean, but because the O2 pulse is delayed (time to flow down the pipe) the damage may already be done. Add in reaction time and you have even more damage before you lift.

On a WOT dyno run typically the A/F graph has to be adjusted by 250-350 rpms.

[plumcrazy]

i asked kevin at underground racing (who knows a thing or 2 about vipers) about the placement of the WB. i bought a set of used belanger headers from one of his customers that had it in the tube coming off of the head about 3/4 way down. and that was the only WB he had. kevin said thats where he always puts them (single) and never has a problem. also said something about keeping it simple...

maybe he since changed his view but that was only a year ago.

i dont personally think ya need 2 WB's. but ive been wrong before

[Steve 00RT/10]

As I understand it, the main function of a crossover pipe is to carry any imbalance of exhaust due to any unequal exhaust pipe length. Other than that, different iterations of a crossover probably produce different sound characteristics. I've always been told a crossover will have the most effect on systems of unequal length. An example would be a transverse mounted engine.

It doesn't make sense to me to mount the WB in a rear crossover which gets only a portion of exhaust flow way down stream (maybe very little in a Viper). ....Seems you are increasing the variables for a bad reading the more bolted joints joints it runs through.

The single tube solution, for Belangers anyway, only came about as a band aid to stop the heater code MILs in newer cars from the stock OEM O2 location. When I bought Belangers in early 2001, they didn't come with a bung up high and MIL lights were abundant.

IMO, it is best to mount the WB (and stock 02) after the collector area in the turn out (factory O2 location) pipe....thereby getting an average from all 5 cylinders in the bank. Using only 1 cylinder is basically fooling the computer. In a perfect world there would be a stock O2 sensor on every cylinder sending a signal back, but that's not practical.

My experience to date shows 1 WB to be sufficient. Burning another one in and capping that bung (like Dan states above) is a good way to have the option to switch occassionally and check out the other side. 23,000 Roe "Hard Charging" miles the last 2 seasons...with a couple track events and some autocrosses thrown in are proof to me that this method works well. Dan and I are pretty much on the same page for WBs, 5 pounders, and tuning.

Steve

[Purdue_Boiler_Viper]

Originally Posted by Steve 00RT/10

As I understand it, the main function of a crossover pipe is to carry any imbalance of exhaust due to any unequal exhaust pipe length. Other than that, different iterations of a crossover probably produce different sound characteristics. I've always been told a crossover will have the most effect on systems of unequal length. An example would be a transverse mounted engine.

It doesn't make sense to me to mount the WB in a rear crossover which gets only a portion of exhaust flow way down stream (maybe very little in a Viper). ....Seems you are increasing the variables for a bad reading the more bolted joints joints it runs through.

The single tube solution, for Belangers anyway, only came about as a band aid to stop the heater code MILs in newer cars from the stock OEM O2 location. When I bought Belangers in early 2001, they didn't come with a bung up high and MIL lights were abundant.

IMO, it is best to mount the WB (and stock 02) after the collector area in the turn out (factory O2 location) pipe....thereby getting an average from all 5 cylinders in the bank. Using only 1 cylinder is basically fooling the computer. In a perfect world there would be a stock O2 sensor on every cylinder sending a signal back, but that's not practical.

My experience to date shows 1 WB to be sufficient. Burning another one in and capping that bung (like Dan states above) is a good way to have the option to switch occassionally and check out the other side. 23,000 Roe "Hard Charging" miles the last 2 seasons...with a couple track events and some autocrosses thrown in are proof to me that this method works well. Dan and I are pretty much on the same page for WBs, 5 pounders, and tuning.

Steve

Steve,

So you welded a bung into the Belanger turnout for the WB. Did you do a second bung for the stock O2 sensor? Where (clock position) did you place the bung(s) on the turnout?

Thanks,
Pat

[ViperTony]

Pat, I'll take pics of what I did for you today but I welded the 02 bungs in the 3 o'clock position(driver's side) and 9 o'clock position (passenger side), near the 3 bolt flange actually, just before the turnout starts. The reason I placed them there was to make certain I'd catch exhaust flow from all 5 tubes. This also seemed to be the only place where the O2 wouldn't hit/interfere with the pickle. With the DC Performance O2 sensors, everything has been fine. I'll post pics this afternoon.

[Purdue_Boiler_Viper]

Originally Posted by ViperTony

Pat, I'll take pics of what I did for you today but I welded the 02 bungs in the 3 o'clock position(driver's side) and 9 o'clock position (passenger side), near the 3 bolt flange actually, just before the turnout starts. The reason I placed them there was to make certain I'd catch exhaust flow from all 5 tubes. This also seemed to be the only place where the O2 wouldn't hit/interfere with the pickle. With the DC Performance O2 sensors, everything has been fine. I'll post pics this afternoon.

Excellent! Thanks Tony. I'd also be interested in seeing how you attached the turnout to the cat. BTW, I have the ROE PCM, so I shouldn't need the DC O2 sensors.