Hello,

Can you let me know if that is best place to install A/F sensor – driver side just before cat.



Let me know as well what is in your opinion best A/F level for 91 Octane Tune with K&N CAI – I guess that should be similar to others so about 12,4 – 12,9?

I am going to install Wide Band A/F gauge and need to set up as well points where the gauge will show me on a color bar I am going lean or rich. What levels set up? What you recommend?

Lean from 13,5?
Rich from 11,5?

 

That is a very bad location for the sensor. The problem is it is on the BOTTOM of the pipe.

The sensors are ceramic and they are heated up VERY hot. With the sensor on the bottom, when you start the car up (say, first thing in the morning), any condensation puddled in the exhaust system can get blown across the hot ceramic and cause it to crack.

In general, O2 sensors are always mounted in the top half of the pipe to prevent water from killing the sensor

When I installed my O2 sensor, I was able to have the bung welded in on the passenger side H pipe in front of the stock front O2 sensor. It was half way between the flange on the h-pipe and the stock O2 sensor, on the top. It's a tight fit, but it will go in there and you will have room to remove the sensor without having to drop the h-pipe.

 

When you were welding the bung did you drop the h-pipe first to do that??

 

Unfortunately. There just isn't NEARLY enough room to drill the hold for the sensor and then weld the bung on. Thankfully, it isn't TOO hard to drop the h-pipe for drilling/welding.

I would recommend that you use a Sharpie to make the location of the new bung before you drop the h-pipe to make sure you get it in the right location. You would be VERY pissed to pull it out, install the new bung only to bolt it all back up and find that you have the sensor pointing in the wrong direction and it will hit the tranny tunnel!

 

Ok I will have to drop it down will be PITA as nuts on manifold looks quite rusty I do not understand why ford did not put here stainless steel nuts and bolts. I will point best location with H-pipe installed before I will take it down but I will install sensor on the driver side.
Thanks for your advise - very helpful.

Can you say something about that A/F ratio levels? When we can say that A/F is going reach and when is going lean - what are the critical levels?

 

That's exactly where I have mine installed and it's been there for about 3 years with no problems. It is on the bottom , but because it's sloping there and not flat , the water doesn't collect ...

 

I had my muffler guy install the bung in like 10 minutes, cost $20.

No drilling required, he just blew a hole using the torch and used a rotary file to clean up the edges.







AutoMeter narrowband O2 sensor installed

 

Hey Bill you have not cats was easy job for you. Any way I am happy your car is already alive.

 

You mean you have it like on the picture I shown where is red dot? from the Bottom of a pipe?

 

Yes , on the bottom ahead of the cats where it slopes upward towards the headers. Since it's on a slope the water doesn't collect there like it would if it were on the bottom further down where the pipe is horizontal. It was installed by Steeda and that's where they put it , and like I said that was about 3 years ago and my sensor is still good ...

 

Ok thank you for that information.

I do not understand why nobody say anything about A/F ratio - did I ask some stupid question?
There is no range for A/F ratio for Mustang GT without supercharger with 91 Octan fuel tune?
Guys say something your gauges are reading something or not??

 

I had the gauge before I was S/C'd and my Steeda tune had it about 12.6 at WOT on the high end , that was with a 93 octane tune for CAI/CMDP/UD Pulleys/Axle Back Exhaust. At idle or just cruising it should read around 14.7 , regardless of your mods. It it won't be a steady reading all the time , but should fluctuate around it ...

 

Just installed and the riding on idle is around 14,7 I will take a ride later today to check on WOT. Any way I found such information.

"The Air fuel ratio is the most common reference term used for mixtures in internal combustion engines. It is the ratio between the mass of air and the mass of fuel in the fuel-air mix at any given moment.

For pure octane the stoichiometric mixture is approximately 14.7:1 or λ of 1.00 exactly.

In Naturally Aspirated engines powered by octane, maximum power is frequently reached at AFRs ranging from 12.5 - 13.3:1 or λ of 0.85 - 0.901."

Ok after ride:
During normal driving I got around 14,5-15. but with hard accelerating its going to about 12,4 with some peaks to 12,1. When I slow down a car with the engine without touching acceleration it goes over 16 - I guess its normal as when you slow down car by engine the fuel is cut to minimum.

 

By the way some pictures

 

It sounds like you're getting good readings ... Yes , when you let off the gas the engine goes very lean , since it has now become an air pump ...