Can Diffuser entrance be wider than space between wheels?

[g-force_addict]

Can the diffuser entrance (the place in the underfloor where the diffusers begin) be wider than the venturi tunnel width between the wheels?

Like this


Doesn't the narrowing after the wide entrance cause air to compress when you actually want it to progressively expand?
Can you overcome this by increasing the tunnel height after the wide entrance so that transverse area progressively increases?

[flynfrog]

Its also getting taller at the same time. Think in 3D

[wesley123]

This is the underside view of the LMP1 and 2 floor. As you can see the entrance is wider than the tunnel itself. Like flynfrog said, it's 3 dimensional.

I think the wider throat helps a bit under yaw.