Nice info!
The old adage that goes "at some point you should not sacrifice breathing for compression " I think is showing up between these two motors .
The added 15 to 20 Intake cfm the 6X heads have over the small valve 16 castings, plus the better Exh Manifolds I think is key here.
The numbers are darn close even with the 1970 motor having more Cam !
__________________
I do stuff for reasons.
|