Looking to upgrade the single Rochester to a dual carb set up on my stock 65 C10. I had initially thought of using a Clifford 4 barrel manifold with a 390 cfm carb. I ran 2 Carter W1`s on my 55 pickup and found the response off idle to be lacking. What would be a good pair of carbs to run on a stock 230 with a split exhaust? Which manifold would be recommended?