I'm thinking along the lines that it's a little unkind to call the Cobra a 'barn door' or a 'brick' when the drag force is related to the drag coefficient multiplied by the frontal area.
OK, given that the drag coefficient of the Cobra is probably north of 0.42, but its frontal area has to be quite small (we're not talking about a big barge here).
Multiply Cd x A for a Cobra and it can't be deserving of the 'barn door' tag, can it?
The first road test of the Shelby's 260 engined Cobra (OK, hotrodded no doubt) gave a top speed of 152mph. Not bad for a 'barn door'
Cheers,
Glen