I attached a couple pictures from my Boss this AM
....everyone's Boss is like this... and I bet all 2011+ Mustangs too.

I wonder if we can REMOVE or CHANGE this big black lower cowl that we can improve air flow OUT of the hot engine bay.

Anyone try anything like this before?

 

never noticed that.. good find... should be a direct replacemnt if you can get the PN.

 

I remember someone saying that they removed this and that it did in fact reduce underhood temperatures along with the Boss 302S Grill.

 

If this is removed would it not increase under hood pressure/air?

Cowl induction hoods have this area open and the effect is an increase in airflow, air flowing into the engine compartment,at the rear of the hood. The cowl is a high pressure area caused by the air stacking up while making the turn upward and over the glass.

So would the desired effect be achieved, additional airflow outward from under the hood if this area were modified? The opposite may occur.

 

Some owners have just removed the rubber seal at the top which seals the hood to the plastic lip of the cowal

 

The statement about the cowl induction hood is right. This is a very low air pressure area and is optimum for the intake (carburated) to get cool clean undisturbed air. There is not enough air flow suction here that suffices to remove engine temps.

 

wonder if that changes with a tiger racing hood

 

No because your getting the air over the forward center of the hood.......absolutly getting the siphon effect at that area.

 

Correct. Removing the gasket or worse the cowl cover won't help when the car is moving. See those slots in the cover? That is where the air gets in for your heater.