A 'high flow' air filter, by itself, makes no difference to the amount of air passing through an engine unless that engine is running at such high output that the intake becomes a restriction to it.
In short, exhausts are similar.
Except that the exhaust gases are under pressure and 'therefore' it's considered a good thing to reduce the 'restriction', to help them escape. But then it's important to consider cam timing, valve overlap, which is designed around certain exhaust characteristics.
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