how large of a carb can perform well on stock 273 commando ?

It's been a year past now........ here is a video of the 65 dartcharger 273 . after I installed headmann headers , a x-pipe and ultraflo mufflers. skroll down and open the big box .. the video is in there..
[ame="http://s446.photobucket.com/user/stroker402/media/3d2cdd52.mp4.html?sort=3&o=21"]Nice Rev Seafoam Tips No Smoke Video by stroker402 | Photobucket@@AMEPARAM@@http://i446.photobucket.com/albums/qq185/stroker402/bth_3d2cdd52.mp4@@AMEPARAM@@446.photobucket.com/albums/qq185/stroker402/bth_3d2cdd52.mp4[/ame]