The impoverished form of an Irish Car Bomb (Bailey's dropped into and chugged from a Guinness). A head on collision is Kahlua dropped and chugged from a Busch Light.

1) Serve a shot of Kahlua
2) Drop into a cup of Busch Light
3) Chug in one gulp
"-Yo, let's do an Irish Car Bomb.
-Nah, that's too classy, I'll take a head on collision"
by InventedHOD April 22, 2009
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