How many seconds does your engine cover take away from the 1/4? But im geussing you dont really show it off though?

In my word...it would take enough away to feel like murder.
And no, nothing to show off here except for screaming horsepower.

Heat is the enemy. ANY heat trapped in the engine bay is bad for performance. Just to give you an idea last time I was at the track I saw an 04 gtp with its cover still on, hood propped open in the staging lanes. Using a laser pointed temp gauge we found out my supercharger was 118 degrees after a run and was almost 200 under the cover. After seeing that I showed him how to take off the cover and he threw it in his trunk. Almost instantly the heat of his supercharger dropped to 150.

You will not see anyone who is looking for max performance from their L67 with the stock cover on. Some people will cut away most of the mass and put a screen in it to help with cooling while maintaing a visual appeal but even this little bit is bad IMO (no offense to those who run them)

I know heat is bad, but was curious if there were any numbers. Maybe I will try riding around with mine off and see if I can feel any difference.

I wish my engine bay was that clean looking.