Here's our lineup of carbs from tame to terrific. On the left is the classic 750 with its choke horn still in place. In the middle is the new Holley Street HP, priced in between the original 750 double-pumper and the new HP on the right. All three carbs are rated at 750 cfm. In the upper righthand corner is a 950-cfm HP Ultra that we also tested, although on our 383ci it offered no power advantage.