For Caterhams:
Overall length:
Roadsport / Classic: 3380mm
Superlights: 3100mm (no spare wheel you see!!)
SV (fatboys version): 3530mm
Overall Width:
Roadsport / Classic / Superlight: 1575mm
SV (fatboys version): 1685mm
All Westfields seem to be one size:
Overall length: 3540mm
Overall width: 1560mm
In other words, pretty small compared to a Scooby (length: 4410mm, width 1730mm).
(Please note I have the Caterham & Westfield catalogues next to my PC- I'm not an anorak, honest
)