Regardless of where it breaks ( I dont recommend you telling Ford "my truck broke while I was at the drag strip") Ford should fix the problem. HOWEVER, there have been horror stories of people with unmodded vehicles (mainly '03 Cobras) getting their warranties voided because of "abuse." I would think with an unmodded vehicle, you should be OK though.
Every manufacture that has voided warrenties for racing on vehicles that they advertise as "performance", "sport" and advertize performance specifications (such as does SVT) has lost in court battles.
Nearly 75% (a number based off of experiance of working at a dealership) of warrenty cases are one by the individual, and not by the manufacture/dealer. Even in the event that the manufacture/dealer was right.