Afr ratio !!

[vic2ory]

I'm running the car with stock tune in it .. And the car running 12.7 at WOT is it good or i should be careful and tune it ..

Cause the car is super fine and no stock or intake and tuned mustang beats me

Im just worried bout if im running lean or nah

Cuse i used to have a chevy and it was safty to run 12.7

 

[20redfire03]

For a N/A I'm pretty sure 12.7 is fine. For a boosted motor I'd say that was too lean.

 

[Healthforhazard]

I get the idea but god thats hard to read.

Edit didnt realize english might not be your first language. sry

 

[vic2ory]

For a N/A I'm pretty sure 12.7 is fine. For a boosted motor I'd say that was too lean.

Yeah it's Only intake and tune

Thnx

 

[AKDMB]

Coyote's run very rich, so like .82-.85 lambda, so I imagine there is some power there. It is on the leaner side, a safety issue, maybe, but with conservative timing it might not be an issue. Hopefully Shaun @ AED or JPC will comment and set us straight. I'm pretty sure from the factory these cars are supposed to run richer than that. The key thing to watch would be your STFT( short term fuel trims) and LTFT( long term fuel trims). These will tell you how far off the car is, if any, fueling wise. So a 1.05 STFT would mean the car is correcting its' fueling by 5%. If your STFT's are off by more than 5% ( factory should really be within 1-2%) , then something is off. The factory tune has safe air fuels, so the STFT's will tell you how closely the car is sticking to the factory air fuel ratio. Low fuel trims means the car is having to do little to no guess work fueling wise. I don't have a 2013+, so I don't know if STFT can be read with track apps, or whatever it's called. If the car starts knocking then you have problems.

Conversion of Lambda into Air Fuel Ratio.


(.82 lambda) × ( 14.08 factory stoich with pump gas and 10% ethanol) = 11.54 Air/Fuel Ratio


(.85 lambda) × ( 14.08 ) = 11.96 Air/ Fuel Ratio

So ideally your WOT Air Fuel Ratio would be between 11.54 and 11.96

EDIT: oh, your car is tuned. Make sure when you say WOT your foot is really to the floor and the car is really loaded up, otherwise WOT fueling isn't really being demanded and the car might appear to be running lean. Best advice is to email your tuner and ask them what they tuned the car run at wide open and they will tell you if you are safe or not.

 

[vic2ory]

Coyote's run very rich, so like .82-.85 lambda, so I imagine there is some power there. It is on the leaner side, a safety issue, maybe, but with conservative timing it might not be an issue. Hopefully Shaun @ AED or JPC will comment and set us straight. I'm pretty sure from the factory these cars are supposed to run richer than that. The key thing to watch would be your STFT( short term fuel trims) and LTFT( long term fuel trims). These will tell you how far off the car is, if any, fueling wise. So a 1.05 STFT would mean the car is correcting its' fueling by 5%. If your STFT's are off by more than 5% ( factory should really be within 1-2%) , then something is off. The factory tune has safe air fuels, so the STFT's will tell you how closely the car is sticking to the factory air fuel ratio. Low fuel trims means the car is having to do little to no guess work fueling wise. I don't have a 2013+, so I don't know if STFT can be read with track apps, or whatever it's called. If the car starts knocking then you have problems.

Conversion of Lambda into Air Fuel Ratio.


(.82 lambda) × ( 14.08 factory stoich with pump gas and 10% ethanol) = 11.54 Air/Fuel Ratio


(.85 lambda) × ( 14.08 ) = 11.96 Air/ Fuel Ratio

So ideally your WOT Air Fuel Ratio would be between 11.54 and 11.96

EDIT: oh, your car is tuned. Make sure when you say WOT your foot is really to the floor and the car is really loaded up, otherwise WOT fueling isn't really being demanded and the car might appear to be running lean. Best advice is to email your tuner and ask them what they tuned the car run at wide open and they will tell you if you are safe or not.

Im running with JLT cai and the reading on my AFR is 12.7 and the car runs pretty good