I went to a Holley 390cfm 4-bbl sitting on a Offy intake for my 250. I had two "B" model Rochester's before and had nothing but trouble with them even with the great input from this site. Love my 4-bbl Holley. Starts fast and easy, a snap to get tuned, pulls lke a tank. Got a warranty for life. Plus it looks bad sitting on an inline.