Not that again! Two-barrel carbs are rated differently, you need to divide the two barrel rating by the square root of two (1.4142) to convert to a four barrel reading. For 1350 two barrel cfm that equates to 955 four barrel cfm. BUT, the carb setup opened the end carbs only as much as the engine needed so I don't think any stock 340 ever used all of the 6-pack capacity.

R.