Afr at full throttle

[Hemiride]

I own a 16 kitty with a 2.85, pulley 775 injectors, 180 t-stat k% n cold air, blowrr spacers and thremo blanket. Tuned on 93.

Question is what AFR should I be running at full throttle? My gauge shows 10.5

 

[Paladin06]

I own a 16 kitty with a 2.85, pulley 775 injectors, 180 t-stat k% n cold air, blowrr spacers and thremo blanket. Tuned on 93.

Question is what AFR should I be running at full throttle? My gauge shows 10.5

I got a 15 with basically the same setup and my tuner has me setup at 11.3 to 11.5 and it makes 14.2 pounds of boost.

 

[jonx96]

I think I was 11.5 to 11.8. When I was on 93. Do you have a data log to share? There are some who will chime in with suggestions after seeing that.
10 seems rich.

 

[parttimer]

2.85 with catless pipes, Id 1000 injectors

 

[vortecd]

I was told you can only go by what you see if you are about 1:1 or close (trans gear) wide open. Lower gears will not be a good read. The good news is 10.5 is pretty rich and safe unlike you saying 12.5

 

[Speedy!]

10.5 is a bit rich for my taste. I'd wanna see around 11.5 on pump gasoline.

 

[jonx96]

I would say it is worth asking your tuner to see what he says.

 

[fumanchu182]

10.5 is a bit rich for my taste. I'd wanna see around 11.5 on pump gasoline.

Exactly what I was about to say. Since stoichiometric on Hellcats is .0722 (FAR, afr would be 1/.0722, ~13.68). Since you want to command 11.5 I'd do 1/x = 11.5 -> 1 = 11.5x -> x= 1/11.5 -> x = .0869

So .0869 - .0722 = .0147 is what you'd like to add for the fuel enrichment tables at WOT.

 

[Speedy!]

The above assumes no other modifier is stepping in like COT. Most custom tunes have that turned off.

 

[Hemiride]

I got a 15 with basically the same setup and my tuner has me setup at 11.3 to 11.5 and it makes 14.2 pounds of boost.

I still run cats but have the mid mufflers removed. I replaced them with vibrant 1794s. I'm making 16lbs of boost. On this setup.

 

[Hemiride]

I would say it is worth asking your tuner to see what he says.

He says 10.5 is normal under boost. But it seems rich to me

 

[Hemiride]

I was told you can only go by what you see if you are about 1:1 or close (trans gear) wide open. Lower gears will not be a good read. The good news is 10.5 is pretty rich and safe unlike you saying 12.5

Would that be 4th gear to 5th shift?

 

[white1]

I generally shoot for 11.6ish on positive displacement blower setups

 

[vortecd]

Would that be 4th gear to 5th shift?

Like 5th or 6th. 6th is 1:1

 

[Hemiride]

When you do a dyno pull, don't they have you in 4th gear?

 

[jonx96]

When you do a dyno pull, don't they have you in 4th gear?

4th will get you close enough. Must people have to do it in 4th because speeds get to high for the dyno in 5th.

 

[Speedy!]

Nah, the AFR reading doesn't have anything to do with what gear you're in or if you have cats or not. It's a direct reading from the front wide band sensors in the exhaust. HPTuners actually displays it as Lambda which is nicer for us E85 folks.

Interestingly the emblem on the dash gauge is Lambda, but the display is in AFR LOL.

 

[fumanchu182]

He says 10.5 is normal under boost. But it seems rich to me

This is normal in the stock programming. Dodge leaves it rich from the factory for safety reasons, what those are, who knows? Mine right now is pushing 17psi on a 11.5 AFR at WOT and she's booking.

 

[Whatknot]

Nah, the AFR reading doesn't have anything to do with what gear you're in or if you have cats or not. It's a direct reading from the front wide band sensors in the exhaust. HPTuners actually displays it as Lambda which is nicer for us E85 folks.

Interestingly the emblem on the dash gauge is Lambda, but the display is in AFR LOL.

Thank you, i was about to type out similarly. 🤜🤛

 

[white1]

Nah, the AFR reading doesn't have anything to do with what gear you're in or if you have cats or not. It's a direct reading from the front wide band sensors in the exhaust. HPTuners actually displays it as Lambda which is nicer for us E85 folks.

Interestingly the emblem on the dash gauge is Lambda, but the display is in AFR LOL.

I was wondering about the Lambda symbol. My 2020 displays AFR a friends 2016 symbol is Lambda (mine is something funky) I figured it was due to his being flex tuned lol