the BR Class 91 is one of my favourite engines. i see them quite a lot in Leeds station and many of them have names on them. im not sure but i know one of them holds the speed record of 161 mph but im not sure if this is still the record for locos. these run on the ECML and WCML so im not fussed what route you do for them. You would make my day if you brought these out.
I believe the Class 91's record was an overall British record at the time (just shading the Advanced Passenger Train) and still stands as the record for a British locomotive as distinct from a multiple unit of some sort. The Eurostars on HS1 do about 180mph day in day out.