Edelbrock 500 vs. 600 cfm fuel milage

gliderider06 said
Do you think, on a stock 318 the eddy 1403, 500cfm carb vs. The 1406, 600 cfm carb give any advantage on fuel economy or just be a moot point?

Super minimal difference.
The engine is going to pull what it can use with either, and a 318 maxes out at around 600 cfm anyway.