"Jeff Strickland" > wrote in message
...
>
> "Dave Plowman (News)" > wrote in message
> ...
>> In article >,
>> Jeff Strickland > wrote:
>> > > >I'm with Dave here. I can't see how a door (and an opening) would
>> > > >add
>> > > >any rigidity.
>> > >
>> > > The 2-door has a larger hole. The 4-door has 2 more holes, but
>> > > there's a metal beam between them.
>> > >
>>
>> > Exactly.
>>
>> So you think any two door has just a sheet of metal between front door
>> and
>> rear wing? The B post on a two door has to be equally as strong as on a
>> four door to prevent the door intruding inwards in a side impact.
>>
>> A door adds little or no rigidity - just weight.
>>
>
> The door adds nothing. The structural integrity is enhance when the door
> openings are smaller. Using this logic, a four door should be stiffer
> because there is an A pillar, a B pillar and a C pillar, and smaller door
> openings. The 2 door only has an A and a C pillar. The theory that dizzy
> and
> I are putting forth is that the 2 door has (perhaps) stiffening added to
> the
> floor pan, and this adds to the cost of the vehicle. Therer is certainly
> stiffening components added to the floor pan of the convertable, but this
> is
> a somewhat different situation than is presented in a hardtop 2 door car.
>
> Having suggested that, another poster suggests that the coupe gets the
> Sport
> Package as standard equipment whereas the sedan has it as an option that
> costs in the neighborhood of $2000. This could also explain the price
> difference.
>
>
>

A 4 door has A, B and C pillars.

The compact has IIRC a standard front door and B & C pillars.

A coupe typically has no B pillar, so the strength of the roof and floor pan
need to be increased.

A drop head coupe has no roof, so the floor has to be greatly strengthened
for the structural rigidity needed in a top class car.