you know that plastic cover on top of hte engine bay fellas...
well i heard that if you remove it then it would act almost like a free mod to your car because it would allow the intake to access more air..

if any of you know the answer please tell me.

 

Yes, Mazda put that cover there to choke the engine and restrict air.

How would the intake access more air if you remove that cover? It's not even under it...

 

yes, the intake is no where near the cover on the engine. not sure where you "heard" this free mod, but it ain't true.