"Way back when" !! I had a '68 390 Torino GT. The original Holley was a POS. I then put on a 3 bbl 950 cfm Holley which ran like a bear. Since I had a '63 406 Tri power setup, and since the engines are virtually the same I decided that this was the way to go - it sure was. I had to play with the carb jetting a bit, but it outperformed any othen carb that I tried - by far. The only problems that I had were power valves - but since they were only about a buck apiece then, bought several at a time. Today, all you need is the $12 check valve mod or one of their purportedly blow proof pieces.