Charts are references to Breathing Better Caption.

Dart 23-degree Iron Eagle Cylinder Head
Combustion chamber 64 cc
Intake port volume 180 cc
Exhaust port volume 77 cc
Intake/Exhuast valve 2.02/1.60 inches
Valve springs (dual) 1.437 inches in diameter
FLOW FIGURES
LIFT INTAKE EXHAUST
0.200 139 114
0.300 193 145
0.400 231 164
0.500 249 172
0.550 253 173