906 vs 452 heads on 440

this may help you decide Cylinder Heads Flow Data at 28" H2O
Manufacturer /Part Number Port/Vol
Intake / Exhaust Valve Size Intake / Exhaust Combust. Chamber Volume .100"
Intake / Exhaust .200"
Intake / Exhaust .300"
Intake / Exhaust .400"
Intake / Exhaust .500"
Intake / Exhaust .600"
Intake / Exhaust .700"
Intake / Exhaust .800"
Intake / Exhaust Average
Intake / Exhaust
Chrysler #452 Iron 200/62 2.080/1.740 N/A - 142/- 208/- 244/-
502 hp 264/-
543 hp - - - 214.5
N/A
1.320
Chrysler #452 Iron 200/62 2.080/1.740 N/A - -/103 -/132 -/143 -/146 -/148 - - -
Chrysler #518 Iron 233/77 - N/A - 159/- 222/- 262/-
539 hp 284/-
584 hp 295/-
607 hp
658 hp 300/-
670 hp - 253.7
N/A
1.288
Chrysler #906 Iron 200/62 2.080/1.740 80 - 142/- 208/- 241/-
496 hp 262/-
539 hp 270/-
555 hp
603 hp - - 224.6
N/A
1.350
Chrysler #906 Iron 200/62 2.080/1.740 N/A - -/98 -/127 -/143 -/150 -/154 -