FAQ : AFR Readings N/a - F/I

[SSSXR]

i had heard that the optimal AFR for internal combustion engines is 14.3

but after reading this post i realize that the best AFR is very situational. thanks

 

[blackx-runner]

My truck is rich I got up to about 11.2 today at WOT and i am not FI......Advice?

Performance mods... TRD intake, DTLT, JBA catback

Wideband. Innovate Lc-1 XD-16 combo ( did initial air calib before installation )

buy my URD MAF cal and lean it out a little bit :top:

 

[SSSXR]

i had heard that the optimal AFR for internal combustion engines is 14.3

but after reading this post i realize that the best AFR is very situational. thanks

 

[XrunnIT]

i had heard that the optimal AFR for internal combustion engines is 14.3

but after reading this post i realize that the best AFR is very situational. thanks

Stoich is 14.65, which is chemically ideal for a thurough burn. Not the best for making power, let alone making power safely.

 

[Venomous_X]

I would get the maf cal, but the x1 is on the agenda....no need to buy twice, when i can save and get the right product the first time david. Sticky me!

 

[ntinhri]

make it lean! duh lol Maf cal bro!

 

[xrunish]

so i saw this on a magazine about a few weeks ago been meaning to post it thought it would be pretty cool to have it http://www.innovatemotorsports.com/products/ot2.php

 

[Murderface]

Of course all these iPhone capable gadgets to monitor ur engine come out RIGHT after I buy a Scangauge II:thumpdown:

 

[Venomous_X]

I think I will need to hurry and save my pennies quickly for the x1. I dont like the idea of being rich and I kinda do not want to buy a maf cal only to take a loss on it when I sell it after saving for the x1. If that makes any sense.....I like the iphone app btw Xrunish....:top:

 

[XrunnIT]

Sticky me!

Done. :top:

 

[ACEE-TL]

hum....I hate reading... So running 12.5 at WOT I'm guessing is not that good???? I guess I'm just gonna bit the bullet and get that bung welded this weekend to get some accurate readings

 

[XrunnIT]

hum....I hate reading... So running 12.5 at WOT I'm guessing is not that good???? I guess I'm just gonna bit the bullet and get that bung welded this weekend to get some accurate readings

12.5 under boost would make me sweat in most cases. If your not knocking, then you're ok. But I would be nervous running that lean on the TRD blower.

I would definitely invest a few $$ in good monitoring if it means saving you a couple thousand $$$ down the road.

 

[5H4D0WD347H]

It all depends on load, knock potential of your particular engine, ambient conditions/fuel quality, and how ballsy you are guys.

Every single person can and will vary.

ALSO its about quenching HEAT to protect the components not just knock.

 

[ACEE-TL]

12.5 under boost would make me sweat in most cases. If your not knocking, then you're ok. But I would be nervous running that lean on the TRD blower.

I would definitely invest a few $$ in good monitoring if it means saving you a couple thousand $$$ down the road.

ok will there be a difference with load? B/c when it read the 12.5 I was sitting in a parking lot not moving. So I'm guessing b/c of lack of movement this could have something to do with it??? You know not have as much cooler air circulating? I have the AEM wideband (thats not installed 100% yet), I need to get the bung welded, so I guess I'll be getting that bung welded this weekend. So I can monitor everything better. So far I haven't noticed any knocking...if it knocks to bad wouldn't I get a CEL????

 

[XrunnIT]

ok will there be a difference with load? B/c when it read the 12.5 I was sitting in a parking lot not moving. So I'm guessing b/c of lack of movement this could have something to do with it??? You know not have as much cooler air circulating? I have the AEM wideband (thats not installed 100% yet), I need to get the bung welded, so I guess I'll be getting that bung welded this weekend. So I can monitor everything better. So far I haven't noticed any knocking...if it knocks to bad wouldn't I get a CEL????

So where you seeing 12.5 at WOT? or at an idle?

How is it installed now if not screwed into a bung?

If its not properly installed, i would take those readings very lightly. For example if your getting clean air over the sensor, then your mixture will come back leaner then it really is. Its critical to have it installed properly before you start making tuning decisions based on information that may or may not be accurate.

As for movement, that doesn't really make any difference into the AFR. The engine load, and other dynamic variables all get put into a formula to determine what AFR and timing advance/retard to run.

 

[ACEE-TL]

So where you seeing 12.5 at WOT? or at an idle?

How is it installed now if not screwed into a bung?

If its not properly installed, i would take those readings very lightly. For example if your getting clean air over the sensor, then your mixture will come back leaner then it really is. Its critical to have it installed properly before you start making tuning decisions based on information that may or may not be accurate.

As for movement, that doesn't really make any difference into the AFR. The engine load, and other dynamic variables all get put into a formula to determine what AFR and timing advance/retard to run.

The the hardward (gauge and wiring) is done. But I don't have the bung welded and the 02 sensor is not installed. The bung and o2 sensor is still in the box that wideband came in.

The 12.5 was @ WOT while I was sitting in the parking lot not moving. I just revved the engine. I got this reading from Vecte's scan gauge

 

[XrunnIT]

The the hardward (gauge and wiring) is done. But I don't have the bung welded and the 02 sensor is not installed. The bung and o2 sensor is still in the box that wideband came in.

The 12.5 was @ WOT while I was sitting in the parking lot not moving. I just revved the engine. I got this reading from Vecte's scan gauge

ahhh... ya, i'd take that with a grain of salt man. I've done some comparing with the SGII and X-1 readings, the AFR is close, but IMO not close enough to be taken to heart. Load is off quite a bit, MAF though is pretty accurate (just slow).

Get your wideband all put together, then lets reassess the situation, and see what's up :top:

 

[ACEE-TL]

yeah...I'm going to get that done saturday. I was putting it off b/c I got that CEL for my cats, and didn't want to weld the bung, change headers and get another one done. So...But I guess like you say better to pay the few extra bucks to monitor everything now then pay big bucks later b/c I didn't spend the little buck to monitor things now. I'll let ya know later this weekend

 

[5H4D0WD347H]

The scangauge seems to be very accurate, just slow to respond.

Keep in mind that there is a delay and you can still read it appropriately.

 

[Venomous_X]

hmm, i need to replace my sensor apparently, im getting all kinds of jumpy readings myself LOL, but I suspected the sensor may be on its last leg before due to mechanic error :motz: I may not be running as rich as I thought, but won't know for sure till I get a new sensor.