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Discussion Starter · #1 ·
So about a month ago i purchased a cobb ap and installed stage 1 93 oct, i was very happy with it but my afr was around 12.2-12.4 on wot pulls. I figured that was a little lean so I tried the stage 2 tune on 93 oct and i now see 11.9- 12.05. Now i know its not advised because of the intercooler but i was wondering if someone could give me input on this.
 

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Direct injection is a different animal than port fuel injection, because the fuel is sprayed directly into the combustion chamber it actually cools down the combustion temperatures. Because of this, and a couple more technical points that I won't get into right now for simplicity sake, you can safely run a leaner AFR and still maintain a safe and effective running engine.
 

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That is a little too lean though. Especially on the stage 1 tune (where he should be). There is a reason why tuners shoot for that 11.7 on WOT. DI cars should be a little rich. I read somewhere in a tuning thread here that there is no extra power to be had by leaning this car out, so it's best to keep safe and avoid letting it go that high. OP I would play it safe and check everything over again, make sure there isn't a hardware issue. If everything seems sound, maybe talk to a tuner and have a custom tune written.
 

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Discussion Starter · #4 ·
That is a little too lean though. Especially on the stage 1 tune (where he should be). There is a reason why tuners shoot for that 11.7 on WOT. DI cars should be a little rich. I read somewhere in a tuning thread here that there is no extra power to be had by leaning this car out, so it's best to keep safe and avoid letting it go that high. OP I would play it safe and check everything over again, make sure there isn't a hardware issue. If everything seems sound, maybe talk to a tuner and have a custom tune written.
I can try to upload a datalog of everything if that would help
 

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I'm not sure how helpful I will be, but it couldn't hurt to have one here for reference. If nothing else, it'd be good to know if it stays lean throughout the whole pull, or if it's just lean for a short period.
 

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Discussion Starter · #6 ·
I'm not sure how helpful I will be, but it couldn't hurt to have one here for reference. If nothing else, it'd be good to know if it stays lean throughout the whole pull, or if it's just lean for a short period.
On stage 1 it dropped to 12.05 briefly then back to 12.4. Stage 2 it dropped to 11.7 briefly then was 11.9-12.05 the rest of the pull both pulls were from 2000-5500 4th gear
 

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Discussion Starter · #8 ·
Any idea if the car was previously modded or was it brand new?
All i know is that the previous owner upgraded the motor mount with a cobb motor mount and a boomba racing bov
 

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Discussion Starter · #9 ·
Bump.
 
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