I installed a stillen intake /CAI and oem Z-tube, as I was putting everything back together, I thought about leaving the engine cover off. But what I noticed was that the engine cover protects the engine bay slightly of heat dissipation. When I pull off the cover I can definitely feel more heat hit me. I'm sure it's slight and probably at the expense of slightly higher Temps under the cover but what I was wondering about, do you think that the engine cover is possibly helping hold heat away from the airbox? Seems to me it would help as an additional heat shield under the hood.

 

That is part of the reason that it comes with the car, it keeps the heat dissipating in a different direction.

 

from all the forums that I am a part of, I see mixed responds about engine cover.
for my case only, I take off the engine cover because I prefer my engine naked