Not knowing what cam you got in the dart, even so I bet you got 100hp+ increase over stock 452's, I think TF's flow around 300cfm at .500" depending on the bench etc., My old Cuda 440 went from 11.3 with stock 906's to 10.7 with just bolted on 2.14/1.81 906's that prob didn't flow more than 260 if that!!...gotta be 1 of the best 440>470 head out out there up to around the 700hp mark with pump gas CR in current 240 style, wait till they get the 270 MW version out for 500 inchers+