A 1970 Rover 3.5 Litre Saloon, DPK797J shows that she has no difficulty keeping up with modern traffic as she completes an anticlockwise lap of Manchester's M60 orbital motorway with ease.
This footage starts at the Shell on the A57 Regent Road - heading first out on the M602 then back into central Manchester along the same road.
This section is from Junction 19 to J15, the start of the Worsley Braided Interchange, passing Simister Island at J18. M60 traffic has to leave the main line of the motorway at Simister. At least the anticlockwise traffic doesn't have to pass through traffic lights. This section of the M60 carries M62 traffic as well and is often very busy.
I couldn't resist testing the kickdown again at Simister! [1:48] and my GPS speedo meant I could overtake the GMP Range Rover at [03:34] without worrying.
The sound was recorded with the built-in microphone - even by modern standards the P5b is a quiet car.
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https://www.youtube.com/watch?v=IY9QqVV0NbI
All is well until we come across a Range Rover with a shit driver behind the wheel.
At [2:37] we drop down to 4th in an effort to pass the pesky 4x4 but the climbing lane is just a bit too short and we will have to put up with wussy brake lights for a few more miles. With the rebuilt engine, we should have gone for 3rd instead of 4th - that way we would surely have overtaken the Chelsea Tractor.
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https://www.youtube.com/watch?v=0-oRvm6CdqY