While more commonly known as a declicious burrito-like Mexican food, a "chimichanga" has been used as far back as 2002 in the New York City region as slang for a unit of time equivalent to approximately 8 minutes.
The specific unit of time a "chimichanga" designates is the subject of debate, as its origin lies in the fact that it takes 1 stoned undergraduate about 8 minutes to consume 1 chimichanga. Most agree that the measurement is exactly 8 minutes 21 seconds, hence "approximately 8 minutes," but only two witnesses were present for the eating of the original chimichanga and both were killed three months later in a freak rhino mauling at the San Diego Wild Animal Park.
Dude, did you SEE Gettysburg? That shit lasted like 30 chimichangas, man!