There are ways to alter the mixture in a single 4 intake, but you gott be willing to do it. This is a place where a 3 or more curcuit carb can shine. We run a single 4 intake and carb on the Vette and they are all within a tenth or so from the beginning to end of a run. There are no damns or obstructions inside the plenum as that would change the volume there. We do it with a combnation of jetting, bleeds, offset boosters and a few other little things to get it that way. Takes work but it can be done to lay perfectly together.

As for he lambda thing yes I get it trust me. I am just stating if he is using a racepak or similar they are based of stoich for pump gas. If you do not change that number in the software for your particular fuels stoich reading then the results you get are not accurate. If he was reading 10-1 based on a 14.7 he could have been much much fatter or leaner(for instance C14 is 15.07-1 stoich) than he thinks he was...FWIW you can change your racepak to read in lambda but finding the lambda numbers for alot of race fuels is not as easy.