My ECM replacement (high pitched whine) was denied

Originally Posted by Sh0velMan

OH, and because this is one of the few cars without an under-hood heat and sound insulating pad.

If it had a half inch thick pad to absorb engine bay sounds you wouldn't hear the TBs at all.

Nissan (incorrectly, apparently) assumed sports car owners wouldn't care that they could hear TB whine, relay chatter and other mechanical noises from their engine bays and decided to save that space that would be needed so they could make the hood lower profile, thus improving aerodynamics and aesthetics.

Originally Posted by Chuck33079

Dynomat makes an underhood liner product for people who don't want to hear these kinds of noise.