Not sure, just bought the heads this winter and going to try a bigger carb, will hopefully find out here in March at a Test n Tune.

Old Combo was a 440, .030 over 10.3:1, .590 solid cam, 440 source heads that had a little bit of porting done, 440 Victor Intake and a 750 DP, 2" TTIs went 10.80's with that combo on a good day.

New combo is a 440 .040 10.9:1, .557 solid cam (smaller than before but short block was already together). Trickflow 240, Victor 440 Intake , going to try the 750DP as a baseline than swap a 850 Proform on it and see how that does and using 1 3/4" TTIs.