 SPOILER:The collision with the train at the end of the film was  accomplished by rigging an engineless Dodge Charger filled with  explosives to a towing cable that was run underneath the train  tracks (the cable and pulley are, in fact, visible in the film). The  towing cable was hooked up to a pulley system, and then to another  vehicle on a frontage road which towed the Charger into the train.  The crash and explosion of the car were actually two separate shots:  one was the actual collision with the train accompanied by a small  explosion, and the second was a larger explosion of the wrecked  Charger staged with the train passing in the background of the shot.