WTF? is this for real?

[flight doc89]

Originally Posted by Strannik

it will lean out your a/f ratios which will give you more power and less fuel consumption, but in the end you might melt your pistons if it leans it out by too much.
better stay away from it
there are heaps of other mods which can be done under 20$

It doesn't lean it out; colder air means denser air means ecu dumps in more fuel to maintain stoich. Colder air readings without colder air means ecu dumps in more fuel than stock fuel map allows = rich mixture