Wow! That's amazing that you got the 500 cfm Edelbrock 1403/1404 carb to run good on a 228!
I have one on a 292 that I'm running unmodified out of the box and it's too much carb for my engine. The 292 is built similarly to your 228 (4 bbl, tube headers, HEI, hi-lift cam, .060 overbore, water heated Offy intake). But with 60 less cubic inches, a smaller bore and smaller combustion chamber I would expect that carb to be waaaaaay too much for a 228. Maybe I'm doing something wrong.
-mnagic mike-
