Believe it or not but way back when during the Cold War American’s were truly petrified of being blown to smithereens by the big bad Russians. It was a chaotic time in this country for both politicians and citizens alike and because of this people did everything in their power to be prepared for war. With the threat of nuclear annihilation looming on the horizon major cities across the United States would hold air raid drills that would supposedly warn us of our impending doom. These drills sometimes included massive sirens like the one you see here. Powered by a 331cid 185 hp Chrysler HEMI’s, the sirens could be heard over a radius of 25 miles. The largest one built had an output level of 176 dB – that’s like 30,000 watts! Below is a video of drag racing legend Don Garlits and his HEMI powered siren, why he has one, who knows. Either way though it’s pretty impressive to hear this thing crank out some noise.