It simply increases the distance the intake mixture travels from the carb base to the combustion chamber. Longer runner length = more velocity, so the cylinder supposedly fills better at low speed. An extreme example of this was the old 413 Chrysler "long ram" intake manifold that put a pair of 4-barrel carburetors outboard of the valve cover, feeding cylinders on the opposite bank. Those engines had neck-snapping torque off the line!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!