I don’t find it extraordinary that small 4 cylinder aluminum engine blocks melted. Some alloys start melting just over 1000 degrees F. Aluminum melts just over 1200 degree F. No doubt there were pockets that hot around cars fueled by all the combustibles in a car. Possible leaving only leaving pieces with iron content.
Plastics are made from oil and like gasoline will burn in the 450 - 550 degrees F range. Aluminum melts at over 1000 degrees F. The video he was talking about shows cars that were turned practically to dust before building 7 fell. They were walking around in the area. It is very strange to say the least. There was no fire in the street at this point yet all the windows are gone, the paint is burned off of the frame. But tires are still in tact. Very weird if you ask me.