anyone out there using a Demon Street Carb

I have a friend that has a 1901 Street Demon Carb 625 CFM on a 340 motor. I have a dynode 340 motor making 375 horsepower with a 1805 Edelbrock Thunder Series 650CFM. He built his 340 motor with the same parts I used except he used a 1901 Street Demon 625 CFM carb, and when he had his motor dynode at the same place as I did, his motor made an extra 15 horsepower and more torque.