Class 455 different carriage profile?

[Tom m]

Can anyone tell me why some of the carriages on the 455 have a different profile to the standard mk3 based ones?

 

[Failed Unit]

They are "PEP" coaches built at the same time as the Merseyrail stock. Someone else i am sure will say why extra coaches were built for them but never used.

 

[30907]

They are "PEP" coaches built at the same time as the Merseyrail stock. Someone else i am sure will say why extra coaches were built for them but never used.

Because the PEP stock started service life as 4-car units on the SW. This thread gives some of the detail.

http://www.railforums.co.uk/showthread.php?t=115830

 

[Feathers44]

They are "PEP" coaches built at the same time as the Merseyrail stock. Someone else i am sure will say why extra coaches were built for them but never used.

They were used when the class 508s ran round SWT (sorry SWR) and Southern land as four car units in the BR days before going to Merseyrail as three car units. The 'spare' cars then went into the second round of 455s that were built (confusingly, the 455/7s where the /8s were built first).