I am sorry but you are not going to put your fuel system out of its efficiency range by an i/h/e/p setup it is not going to happen. Not to mention out vehicles run rich from the factory, when I dynoed the car both times the air/fuel was around 13.6 maybe I will put another bung in my exhaust and hook up my wideband. then go from there!

 

I use a velocity stack (venturi) on the air filter for my S2000.

It increases the speed of the incoming air as it passes through the stack. It has nothing to do with ram air, or which direction the stack is pointing. The air is accelerated due to the shape of the velocity stack.

-Pete