Quote Originally Posted by SpeedDreamz
Ask Sam Mahdavi what it is for. A couple years ago in St. Louis it was about 150 degrees and his popoff blew on a nitrous bottle, it busted his blowdown and shattered his back glass. I was pit'd next to him and it scared the crap out of me.
Exactly. His back window was shattered and it sounded like a shot went off. It's attached to the main valve as a safety release when the pressure gets too high. Sam's did because of the heat coming thru the untinted rear window. If you have the nitrous in the trunk by itself and you don't use a heater on it, you should be fine for street type use. The blow down is a must in the race car where there is nothing between the bottle and the driver, besides the fact that it's a race requirement.