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Discussion Starter · #1 ·
What is everyone's cruising AFR? Mine is consistently above 15.0. It likes to hang out at 15.14 and 15.29 a lot. And my STFT is high as well at around +9.0-10.0 only when cruising. But at idle my numbers look good. My only engine mods are fswerks cool flo oem intake with green filter, a jbr OCC and Cobb ap3 with fswerks stage 1 tune. Do I have a problem?



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mine is usually at 14.85-15 on my ap3 so id say you should be ok
 

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On cruise I would imagine a proper tune with timing could easily support AFR's up to 18:1 with out detonation. We have DI engines and cruising should be a no or low load situation, but I'm just thinking out loud.

However Stoich is 14.7:1 and I am quite confidant that 15:1 would never hurt our cars under the situation described by OP.
 

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Discussion Starter · #5 ·
Thank you for all the replies! I kinda figured being under little load, there might be a slight lean condition if that's even what we wanna call it since it's so little.

And it normal at all other times. Under full boost I'm at mid to high 11's. So no worries of going lean in boost.

Anywho, I've just never been able to monitor AFR before so I just wanted to make sure.


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high 11's at 100% throttle on high boost is kinda lean. 12:1 is more of a target for NA full throttle. 11:1 is more of a target for boosted cars. of course each car will be a lil different.
Thank you for all the replies! I kinda figured being under little load, there might be a slight lean condition if that's even what we wanna call it since it's so little.

And it normal at all other times. Under full boost I'm at mid to high 11's. So no worries of going lean in boost.

Anywho, I've just never been able to monitor AFR before so I just wanted to make sure.


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Discussion Starter · #7 ·
high 11's at 100% throttle on high boost is kinda lean. 12:1 is more of a target for NA full throttle. 11:1 is more of a target for boosted cars. of course each car will be a lil different.
Thank you, still kinda learning all the values. After paying more attention the lowest I get is about 11. And seems to hold more consistent mid 11's until the turbo starts running outta breath then I'm seeing about 12.0-12.2. At least that's what I noticed earlier


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