he perfect intake is pretty much unattainable:
-straight rammer via straight tuned intake tubes, with Direct injection, no
butterflies or anything in the way-
Whatever you put into the way of this perfect intake will increase the
pressure drop: curved intake tubes, butterflies, manifoldboxes, any turns
the air has to take, and eventually an airfilter if you use one.
Ramair will work to alliviate some or all of that - nothing specifically on
airfilters here.....

Correct me if I am wrong, please!

Thomas Jakits

Thomas, you got everything right except one. You CAN and DO get positive pressure past the filter on a ram air box. As you mentioned, a lower pressure than without the filter, but increased pressure nonetheless. The larger the filter the lower the pressure drop of course.

 

Bill Jepson