If you want a free Mountune airbox, remove your stock airbox, and cut the bottom out of it. This effectively creates an unlimited plenum intake which draws cold air from underneath/at the front of the car.
Having taken measurements of the Mountune box, the only benefit is having a shiny piece of metal that effectively conducts heat into the intake tract.
I used a dremel, there are other methods. Takes about 10 minutes including airbox removal. Decent gain of sound and 5whp/8lb ft tq on a mustang dyno with the Cobb stage 1 91 tune running 93 octane.
Having taken measurements of the Mountune box, the only benefit is having a shiny piece of metal that effectively conducts heat into the intake tract.
I used a dremel, there are other methods. Takes about 10 minutes including airbox removal. Decent gain of sound and 5whp/8lb ft tq on a mustang dyno with the Cobb stage 1 91 tune running 93 octane.