The Dealership Data Book for '71 shows a net rating for the high compression 340 of 230@5000 and 310@3200.
https://www.hamtramck-historical.com/images/dealerships/DealershipDataBook/1971/71_Valiant_Duster_14.jpg
RPM peaks are different, even though the '74 360 4bbl used the same cam. So I...