Ford Repair: I have a question that no..., crank pulley, serpentine belt

Question
I have a question that no person as of yet can answer.I own a 1985 ford mustangtwo door hatchback.It has no smog pump and has a performance crank pulley.Need to know what length serpentine belt is needed for the application?Still has power steering and a.c. pulleys.Belt that's now existing is too long,making idle arm bottom out.

Answer
Stuart-

  Off the top of my head I don't know...but there's an easy way to find out.  Just get a roll of string or something similar and start at one point and have someone route the string over the pulleys in the same route the belt will take.  Make sure the string is fairly tight around all of the pulleys and wind it around to where you started.  Measure that length and that will tell you how long the belt needs to be.  Hope this helps.

Steve