I never believe that an intake with the same maf diameter will make the car run crazy lean.
the fact is the air volume has to go pass the maf and some of the air has to be calculated. the car would not run if it would not true, but still could change the readings to a certain degree, but part of that is take up by long term fuel trims.
a cel will only come on if you peg the learned fuel trims to max i believe around 10-15% difference.
if the car was already tuned with proper a/f ratios that are leaner than stock and close to the limit then you put an intake on you could throw the car into some super lean issues.
With all that said. Im still a fan of the STOCK INTAKE. they are good for 300+whp and plenty for the stock turbo. the only time i would go change my intake would be if i went to a 70mm
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