My younger brother snatched my 750 Holley DP while my 383 was being rebuilt in the mid 80's.
Cranked his factory 70' 340 up big time!
Once found I took it back and gave him the 650 Holley DP.
Seems most later 340's were running larger TQ carbs. Story is the 340 in the right set-up is very Hungary! JMO!