440 build

A 600 Holley is small for a 440. You should look into something different. I would be happy to fix you up a nice thermoquad. They do require some learning to tune but they are great carburetors.
I agree with that,cant beat a TQ when tuned..superior perf and decent mpg's..are a little tricky to learn but worth the end result..have a 360 ramchgr had a TQ that needed a kit so I put on a new 600 edelbrock and ran ok but the perf wasnt as good and the mpg's went from 16-17 down to 10-11,so guess what got fixed....