A/F ratio question

[amtrucker22]

I will put my truck back to stock tomorrow before I go to work. I will then compare the values with the ones already posted.

Missed out on dyno time today, had to take the son to get the H1N1 mist.

 

[BurntRubber]

you need to get down into the 12's on that a/f...

 

[BurntRubber]

Just curious as to where your A/F sensor is located on the exhaust, in front of the cats?

most put a bung on the headers

 

[OSO]

most put a bung on the headers

Agreed, just curious if he is getting a lean reading because his are further back (behind the cats).

 

[amtrucker22]

Agreed, just curious if he is getting a lean reading because his are further back (behind the cats).

The bung is about 1 1/2 feet behind my high flow cat on the driver side (had to go check).

Is this possibly why I am getting a semi lean condition? I will be able to move it back to the stock tune tomorrow and see if I get the same numbers. I do plan on taking it to the dyno where I can compare to what they read.

 

[TNVIPER]

The bung is about 1 1/2 feet behind my high flow cat on the driver side (had to go check).

Is this possibly why I am getting a semi lean condition? I will be able to move it back to the stock tune tomorrow and see if I get the same numbers. I do plan on taking it to the dyno where I can compare to what they read.

Being behind the cat will give a slightly leaner reading...maybe .1 to .3....you are off way more...........

 

[OSO]

The bung is about 1 1/2 feet behind my high flow cat on the driver side (had to go check).

Is this possibly why I am getting a semi lean condition? I will be able to move it back to the stock tune tomorrow and see if I get the same numbers. I do plan on taking it to the dyno where I can compare to what they read.

When you get a chance just move the sensor to the header so that you can get a better reading and like everyone said stay out of it till you know for sure.

 

[SANTEEN]

When you get a chance just move the sensor to the header so that you can get a better reading and like everyone said stay out of it till you know for sure.

So idealy, the sensor should be placed before the cat? Not downstream (after) the cat?

 

[Ironhead]

take your cats off then you dont have to worry about it

even justins mid with high flows on it have the bung for a/f in front of cat

 

[OSO]

So idealy, the sensor should be placed before the cat? Not downstream (after) the cat?

Yes "I" have not ever heard of anything different .

 

[Ironhead]

well how did the intervue go ????

 

[VENOMOUS1 RACING]

take your cats off then you dont have to worry about it

even justins mid with high flows on it have the bung for a/f in front of cat

Y'all are all right for the most part. Do not install directly on the headers though. Should be a foot after collector and no more than about 4 feet from collector to get accurate readings from the 5 cylinders. Too close doesn't get an average bank a/f ratio and too far back and you get lean due to cats only by tenths of a point and further can get reversions of clean air pulled in from the tailpipe. Dynos that place a wideband inyour tailpipe are getting very inaccurate readings and usually over fatten the a/f which is much safer but some usable safe power left on the table. A wideband and accurate datalogging for KR is the proper way to tune!

 

[Dom426]

13-14 na that isnt lean i dont thnk

 

[Tooloe]

13-14 na that isnt lean i dont thnk

i dip into the high 11's N/A and mid 10's on spray i think i'm a little fat though i'll see if i can't get a video tommorow

 

[Dom426]

my shit is 10.9 11 wot throttle with 22psi boost i think 14 at wot on an na engine is safe unless this thing is makin boost but i couldnt here it in the video

 

[Dom426]

i dip into the high 11's N/A and mid 10's on spray i think i'm a little fat though i'll see if i can't get a video tommorow

well i think your s is to rich

 

[TNVIPER]

13-14 na that isnt lean i dont thnk

What do you know about N/A....LOL..

 

[Ironhead]

mine dips into the mid elevens when i first floor it but as the rpms go up i come up to 12.2 or so :dontknow:

 

[Tooloe]

well i think your s is to rich

yeah i'd prob be able to make a little more power if my tuner will pull the fuel back a hair...also running a motor to fat can hurt it also just like leaning it out ..except you can put fuel inbetween the rings on the pistons and it'll blow them suckers off! lol

 

[Dom426]

yeah i'd prob be able to make a little more power if my tuner will pull the fuel back a hair...also running a motor to fat can hurt it also just like leaning it out ..except you can put fuel inbetween the rings on the pistons and it'll blow them suckers off! lol

fuel wash i know i have built over 500 race motors