More warp drive scotty

[Desmondo]

Dear fellow birlingo peeps .It has come to my attension on many a motorway that my happy and faithfull MK 1 2002 runs out of steam at about 70mph. Ok so it takes a ten mile run way and half an hour to get there, Its an ex forestery van so im guessing and hoping its been restricted. she has plenty of torque and average m.p.g for an old bus like her only 96000 ..and serviced ..What do I look for under the bonnet to comfirm she has been restricted . Kind regards Desmondo.