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Old 04-24-2012, 10:47 PM   #10
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Originally Posted by JSR84 View Post
Well first off lets use some more realistic numbers for an intake. Air modification, particularly intakes screw with the MAF calibration. In closed loop its not really an issue because the ECU creates fuel trims to compensate however, when in OL the ECU ignores the fuel trims and fuels totally based of the mass air reading from the MAF. If the MAF isn't calibrated correctly the engine doesn't hit its targeted A:F. In some cars it can be a big issues and cause CEL's, in others its not that big of a deal. I prefer to provide the ECU with the correct information to fuel the engine appropriately. When you start compounding modification without making any adjustments to the tune, you start compounding the fueling errors etc.
Right and wrong at the same time... What if I tell you im running 14.5-15.2 during load tests on a dyno? Car is still running exactly how it should. Now only if this dyno wasnt for emissions testing and was for dynoeing cars I would tell you more. But full load im at 12.5-12.7 which is right where it should be if not a little rich.

I think the car is running just fine.

EDIT: On God No LOL 30+ from full race exhaust and intake without a tune.
2012 Audi Q7 TDI S Line ABTuning 391whp588wtq
01 Turbo Focus 300+ whp
2012 Focus 19" Niches, AEM CAI, F2 Race Header, 3" Borla Dual Exit, H&Rs, Eibach Sways 183whp157wtq
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