Edelbrock/Chapman 6129
Intake Port Volume: 277cc
Exaust Port Volume
Chamber Volume 61cc
Valve sizes and Lengths
Intake Valve 2.150 12° X33° 5.540L 2.020 with std ret and +.050 Lock
Exhaust Valve 1.625 25° X 5.560L 2.020 with std ret and +.050 lock
Flow Figures @ 28"
Intake Exhaust
.100 70 53
.200 141 105
.300 212 166
.400 273 204
.500 315 227
.600 343 237
.700 355 242
.800 357 251
Extra Info These are actual flow numbers. They have not been inflated. Exhaust ports flowed without any type of flow pipe.

Erik, these heads are one step up, better are worse numbers??? The difference between int. and exh. seems to be increasing?????