I have dyno tested and raced several of the Holley 950 HP, which actually only flowed 880 CFM on a super Flow flow bench, on several cars and motors, all of them worked very well I have seen more HP on a engine being dyno tested using a 850 BG Speed Demon(flowed 910 CFM on the same flow bench the same day as the Holley 950 HP and another BG Mighty Demon 850 with annular boosters, the Mighty Demon did not flow as much as the Speed Demon did that day on that bench also I'm sure the annular boosters contributed to that I dnyo tested both BG 850 on the same motor within twenty minutes of each other with no other changes using the same gasoline and oil and water temps to keep the test accurate. both carbs. had the stock jetting in them, the Speed Demon made more HP and torque that the Mighty Demon did The standard Holley 850 DP usually flow 900+ CFM stock with the choke plate removed I have several of them(used ones with new kits in them) in stock. If you want to try one PM me