Downsides to removing air inlet pipe?

[perseuss69]

Removed the air inlet pipe just to try it, and the car sounds way better at higher revs. So now I'm wondering, are there any downsides to removing it? It's all before the air filter and MAF, so shouldn't affect much. Only thing I can possibly think of is sucking in hotter air since the intake hole is now nearer to the engine? Also thought I heard a strange windy noise when it wasn't really that windy outside. Not a constant sucking per se but intermittent blowing.

I'm referring to part number 7 in the picture.

[MrTrendizzle]

That part directs cold air in to the airbox. Without it your car is sucking in warm engine bay air.  

Engines like COLD air as it's more dense than warm air. Imagine trying to cool your drink with an ice cube vs steam. Ice cube is dense and works better.  

If you want that vroom sound just replace the filter with a cone filter (Be sure to get one with a short bit of pipe. eBay has loads for like £15) or splash out and get the full setup.