Adding K&N counterproductive?

[Jason Surprise <jmsurpri@xxxxxxxxxxxxxxxx>]

I have heard that removing the air box and adding a K&N cone actually
reduces performance because the air that is used is from the engine bay,
which can be of much higher temperature than the air from outside.
If you have a K&N cone in your bmw, can you comment on the effectiveness
of it and if you have experienced the problems described above?

Thanks,
Jason
94 325i 

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