Need info on slant six engine

To get the full benefits of a 4 bbl on a slant, you should upgrade the cam and exhaust to complement the 4 bbl intake...
I have had a couple 4bbl slants, one rock stock, the other with headers only. The only problem I've encountered was that the headered one's PO had installed a 750 dp. So first thing I did, was try a 625 I had from a 318, still too big. So I bought an electric choke carter 500. Just right. I think a 400 to 500 carb would be just fine on a stock sl6.
that being said, I have no immediate plans to put one on my current 66 cuda. It's just fine the way it is, at least mechanically.