It would also seem that the engine would significantly increase the temperature of the air inside the airbox. A heatshield above the engine would probably be advantageous... or just relocate the heatbox infront of the engine and have a single pipe going back from there to the throttle body. That would probably increase midrange torque most significantly but at the expense of throttle response. That would probably kill the low end, though, seeing as how the car already runs extremely lean from 0 to about 2500 RPMs.