This may seem like a silly question but "so what, its not the first"
If the viento has a wider wheel base than the velocity, how can it use the sierra diff ,drive shafts and hubs or am i missing the obvious.

Wheelbase is the distance between the front and rear wheels.

The Viento is the fat-bastard version?

Presumably it has longer engine bay and/or cockpit?

Ok
Should of said tracking,
Luego Quote:
Viento
Length centre to centre 2700mm, Width at rear centre to centre 1610mm, Width at front centre to centre 1520mm
Velocity Xt
Length centre to centre 2400mm, Width at rear centre to centre 1490mm, Width at front centre to centre 1350mm

Possibly because the Viento has a negative offset on the rear wheels moving the rear wheels outwards from the hubs producing a wider track along with wider rear wheels....