Emissions are tested on a standardized driving cycle that doesn't include full-throttle acceleration, so emissions at full throttle aren't counted. Which is reasonable: high-performance cars spend only a tiny fraction of their time at full throttle so it doesn't contribute much to overall emissions.
> Emissions are tested on a standardized driving cycle that doesn't include full-throttle acceleration
Depends on the car. See Supplemental Federal Test Procedure US06[0], required by the EPA for light-duty vehicle certification since 2007.
It is also largely irrelevant in the real world: nobody is going to tune a car to have mediocre part-throttle performance but then go all-out on full-throttle.
It has a 10 second 0-50 mph section, which for the kinds of cars we're talking about (those that people might buy aftermarket performance ECUs for) isn't close to full throttle.
