O2 sensors
 

In Stock Eliminator on a car running multiple carbs.
Can anyone shed light on running O2 sensors?
Are you running one in each collector or one in each header tube?

Re: O2 sensors
 

For sure if you run sensors on primary tubes particularly on something dual plane, you are going to get readings all over the map. Doing the primaries is going to give you ideas about how bad the fuel distribution is but not really the best choice for overall jetting decisions. The collector is the best compromise and where most people run them. Make sure you locate them far enough upstream to not get readings from the open exhaust reversion.

Jim Caughlin
SS 6019

Re: O2 sensors
 

As a guy that runs 3 multi-carburated cars I have found both on the dyno and on the track to truly tune you need one in each primary. The collector O2 work but is an average of 4 cylinders and you can still.be way off. If you do run 8 make sure you have lots of battery reserve!!

Darcy Clarke
6254
SS/EA A/SA

Re: O2 sensors
 

Yup, when I checked O2 on primaries, I have 2 lean cylinders and 2 rich cylinders so O2 on collector averages everything out and says things are OK. In a SS application, there is the ability to possibly modify the intake and improve the situation, a lot tougher in Stock but maybe some creative corner jetting might help?

Re: O2 sensors
 

You might also play with varying the plug heat ranges.

Re: O2 sensors
 

Darcy, The car is running a 16 volt system with alternator. Is battery reserve still a concern?

Re: O2 sensors
 

One other comment on O2 sensors, they don't like leaded fuels so accept that they don't last for long periods of time. There is no solution to this so just accept them as a disposable item.

Re: O2 sensors
 

I run a 12 volt system and run 2 batteries do lots of reserve, not sure with 16 volt.

Yes on my stocker the max wedge intake presents the challenge, better tuners can figure ot out without but I chose to run 8 O2 sensors on the dyno and tuning was much easier and picked up good power.

Darcy Clarke
SS/EA A/SA

Re: O2 sensors
 

I was going to ask if you ran them in the Hemi while it was in the car.
The reason I asked the original question was, my engine builder is going to run 8 of them on the dyno. I just didn't know if we should run them while in the car. Things on the driverside will be tight. So I had thought about the collector instead. It sounds like we will put 8 in.
Thank you for your help.

Re: O2 sensors
 

Thank you everyone for the help.
Any help getting this 6 pack dialed in is greatly appreciated!

Re: O2 sensors
 

Both my cars are Max Wedge Cars and I have ran all 8 on the dyno and in car on the stocker because of the intake. I have a 6 pack car I only used 2 O2 sensors on the Dyno.

Darcy Clarke
SS/EA A/SA

Re: O2 sensors
 

It looks like your on the right track.

Re: O2 sensors
 

What are the signs that the O2 sensors may be bad? I have a lot of runs on mine.

Re: O2 sensors
 

They go nuts when bad so no mistaking when it happens.

Re: O2 sensors
 

Ive been running the same sensor on mine for probably 5 or 6 years and no issues on 110 VP.

CLark

Re: O2 sensors
 

I have all 8 on both of my cars. I sent them in to Race Pack to get checked. They said I needed to replace a few of them because they were slow reacting. My suggestion is to send them in every 2-3 years to get checked.

Re: O2 sensors
 

Hey Larry, I sure hope so. I want this thing to run...

Re: O2 sensors
 

Great advice from Eric Bell, due living in Canada and expensive shipping I bought a tester for O2 sensors from Performance Trends its not cheap but its an easy way to ensure your getting good data.

Darcy Clarke
SS/EA A/SA