messing around on Wallace and was playing with optimum intake runner length and after i put in engine size 493, cylinders 8 and peak torque rpm (i guessed) and put 5200.

it say my optimum runner length is 16.5" long! and runner area of 3.63"

as bizzare as that sounds, i think weiand sells a spacer to put in between the runners and plenum. i just might get these carbs over my roof yet

http://www.wallaceracing.com/runnertorquecalc.php

what do you think about that?