Max rpm 360 magnum ???

When cash for cluckers happened we had a ton turned in to the dealership I work at. We were send instructions and silica sand from the government on how they wanted us to permanently disable the engines. "Put the silica sand in the oil and Rev in neutral until the engine stops". The magnums, 360s and 3.9L V6s were the hardest ones to kill. The magnums would sit there and scream at there max rpm for over 10 minutes with sand in the oil. All other the engines never lasted more than 3 minutes with the sand in them.