The best replacement for cold air is short ram.

The best alternatives to cold air are rated as following:
★★★★★  short ram
★★★★  warm air
★★  hot air humidifier
★★  warm air humidifier
★★  short ram intake
★★  ram air
★★  hot air
★  hot air intake
★  ram air intake
★  short ram civic
★  ram intake
  hot air density
  stock intake
  ram
  cold water
  v2
  short ram wrx
  short ram rsx
  warm air intake
  short ram 350z

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Speaking about cold air, one probably shouldn't forget about fan.

Other search terms related to cold air and their ratings are:
★★★★★ fan
You have in mind a companion for cold air and it is not yet here? Propose!



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cold air
short ram
warm air