Most motorcycle carbs are variable venturi carbs, maybe like what
SU would have made if they had continued developing carburetors. I
think the ideal setup would be

intake from some part of the front of the car that's higher pressure
and not going to suck in lots of water feeding a large plenum inside
like what is on the d-jet (maybe larger, with air horns inside it
going to each runner) then in the middle of each intake runner, just
ahead of the intake valve, I'd put one carb on each runner.

Such a setup would be pretty much like a weber carb, but using a
variable venturi carb instead of the complex crazy stuff that is in
the webers. Oh, and it is also totally, wildly silly to talk about
such things because chances are a modern FI setup (even a trivial,
simple one like SDS or megasquirt) using a D or K jet manifold will
yield something that works better 99% of the time (though may have
slightly worse throttle response). But it wouldn't look or sound as
cool as 4 motorcycle carbs...
chris